Retrieval of material from vessel lumens

ABSTRACT

Devices for removing clot material from a blood vessel lumen and associated systems and methods are disclosed herein. A clot retrieving device may include, for example, an elongated member, a cover having proximal, intermediate, and distal portions. The cover may be slideably coupled to the distal region of the elongated member at a connector. The cover may have an inner layer and an outer layer. The inner layer may have (a) a first cross-sectional dimension at the proximal portion of the cover, (b) a distally increasing cross-sectional dimension along the intermediate portion of the cover, and (c) a second cross-sectional dimension at the distal portion of the cover, wherein the second cross-sectional dimension is greater than the first cross-sectional dimension. The outer layer may have a cross-sectional dimension that is generally constant along the distal portion and the intermediate portion of the cover.

TECHNICAL FIELD

The present technology relates generally to devices and methods forremoving obstructions from body lumens. Some embodiments of the presenttechnology relate to devices and methods for removing clot material fromblood vessels.

BACKGROUND

Many medical procedures use medical device(s) to remove an obstruction(such as clot material) from a body lumen, vessel, or other organ. Aninherent risk in such procedures is that mobilizing or otherwisedisturbing the obstruction can potentially create further harm if theobstruction or a fragment thereof dislodges from the retrieval device.If all or a portion of the obstruction breaks free from the device andflows downstream, it is highly likely that the free material will becometrapped in smaller and more tortuous anatomy. In many cases, thephysician will no longer be able to use the same retrieval device toagain remove the obstruction because the device may be too large and/orimmobile to move the device to the site of the new obstruction.

Even in successful procedures, a physician must be cautious to preventthe walls of the vessel or body lumen from imparting undesired forces toshear or dislodge the obstruction as it passes through the vasculatureduring removal. These forces have the potential of fragmenting theobstruction. In some cases, the obstruction can simply break free fromthe retrieval device and can lodge in a new area causing more concernthan the original blockage.

Procedures for treating ischemic stroke by restoring flow within thecerebral vasculature are subject to the above concerns. The brain relieson its arteries and veins to supply oxygenated blood from the heart andlungs and to remove carbon dioxide and cellular waste from brain tissue.Blockages that interfere with this blood supply eventually cause thebrain tissue to stop functioning. If the disruption in blood occurs fora sufficient amount of time, the continued lack of nutrients and oxygencauses irreversible cell death (infarction). Accordingly, it isdesirable to provide immediate medical treatment of an ischemic stroke.To access the cerebral vasculature, a physician typically advances acatheter from a remote part of the body (typically a leg) through theabdominal vasculature and into the cerebral region of the vasculature.Once within the cerebral vasculature, the physician deploys a device forretrieval of the obstruction causing the blockage. Concerns aboutdislodged obstructions or the migration of dislodged fragments increasesthe duration of the procedure at time when restoration of blood flow isparamount. Furthermore, a physician might be unaware of one or morefragments that dislodge from the initial obstruction and cause blockageof smaller more distal vessels.

Many physicians currently perform thrombectomies (i.e. clot removal)with stents to resolve ischemic stroke. Typically, the physician deploysa stent into the clot in an attempt to push the clot to the side of thevessel and re-establish blood flow. Tissue plasminogen activator (“tPA”)is often injected into the bloodstream through an intravenous line tobreak down a clot. However, it takes time for the tPA to reach the clotbecause the tPA must travel through the vasculature and only begins tobreak up the clot once it reaches the clot material. tPA is also oftenadministered to supplement the effectiveness of the stent. Yet, ifattempts at clot dissolution are ineffective or incomplete, thephysician can attempt to remove the stent while it is expanded againstor enmeshed within the clot. In doing so, the physician must effectivelydrag the clot through the vasculature, in a proximal direction, into aguide catheter located within vessels in the patients neck (typicallythe carotid artery). While this procedure has been shown to be effectivein the clinic and easy for the physician to perform, there remain somedistinct disadvantages using this approach.

For example, one disadvantage is that the stent may not sufficientlyretain the clot as it pulls the clot to the catheter. In such a case,some or all of the clot might remain the vasculature. Another risk isthat as the stent mobilizes the clot from the original blockage site,the clot might not adhere to the stent as the stent is withdrawn towardthe catheter. This is a particular risk when passing throughbifurcations and tortuous anatomy. Furthermore, blood flow can carry theclot (or fragments of the clot) into a branching vessel at abifurcation. If the clot is successfully brought to the end of the guidecatheter in the carotid artery, yet another risk is that the clot may be“stripped” or “sheared” from the stent as the stent enters the guidecatheter. Regardless, simply dragging an expanded stent (either fully orpartially expanded) can result in undesired trauma to the vessel. Inmost cases, since the stent is oversized compared to the vessel,dragging a fixed metallic (or other) structure can pull the arteriesand/or strip the cellular lining from the vessel, causing further traumasuch as a hemorrhagic stroke (leakage of blood from a cerebral vessel).Also, the stent can become lodged on plaque on the vessel wallsresulting in further vascular damage.

In view of the above, there remains a need for improved devices andmethods that can remove occlusions from body lumens and/or vessels.

SUMMARY

At least some of the embodiments disclosed herein are devices, systems,and methods for retrieving clot material from a blood vessel lumen. Forexample, some embodiments are directed to a clot retrieving device thatincludes an elongated shaft configured to be intravascularly positionedat or adjacent clot material within a blood vessel lumen, and aretrieval assembly coupled to a distal region of the elongated shaft.The retrieval assembly may include a flexible cover and a capturestructure. The retrieval assembly may be deployed within the bloodvessel lumen at or near the clot material such that the capturestructure engages or otherwise becomes enmeshed with at least a portionof the clot material and at least a portion of the cover pressesoutwardly against the blood vessel wall proximal of the capturestructure. Pulling the elongated shaft proximally everts the cover overthe capture structure such that the cover at least partially ensheathsthe capture structure and associated clot material. The retrievalassembly can then be withdrawn to remove the clot retrieval device andassociated clot material from the patient.

In at least some embodiments of the present technology, the cover mayhave proximal, intermediate, and distal portions. The cover may beslideably coupled to the distal region of the elongated member at aconnector. The cover may have an inner layer and an outer layer. Theinner layer may have (a) a first cross-sectional dimension at theproximal portion of the cover, (b) a distally increasing cross-sectionaldimension along the intermediate portion of the cover, and (c) a secondcross-sectional dimension at the distal portion of the cover, whereinthe second cross-sectional dimension is greater than the firstcross-sectional dimension. The outer layer may have a cross-sectionaldimension that is generally constant along the distal portion and theintermediate portion of the cover. When the capture structure isreceived in the cover, a first portion of the inner layer may bedisplaced radially outward to accommodate the capture structure, and asecond portion of the inner layer, located distal of the first portion,may remain collapsed radially inward to form at least a partial closuredistal of the capture structure.

The subject technology is illustrated, for example, according to variousaspects described below. Various examples of aspects of the subjecttechnology are described as numbered clauses (1, 2, 3, etc.) forconvenience. These are provided as examples and do not limit the subjecttechnology. It is noted that any of the dependent clauses may becombined in any combination, and placed into a respective independentclause, e.g., clause (1, 14, 27, etc.). The other clauses can bepresented in a similar manner.

1. A clot retrieving device, comprising:

-   -   an elongated shaft having a distal region;    -   a capture structure having a proximal portion coupled to the        distal region of the elongated shaft and a distal portion having        a distal terminus; and    -   a cover having a first portion coupled to the distal region of        the elongated shaft and a second portion extending from the        first portion, the cover having a first configuration in which        the second portion of the cover extends proximally from the        first portion, and the cover having a second configuration in        which the capture structure is at least partially ensheathed        within the first portion of the cover and the second portion of        the cover extends distally from the first portion, and in the        second configuration the second portion has (a) a first region        distal to a distal terminus of the capture structure, the first        region tapering radially inwardly in a distal direction, and (b)        a second region extending distally and radially outwardly from        the first region.

2. The clot retrieving device of Clause 1 wherein, in the secondconfiguration, the second region of the second portion extends distallyand circumferentially radially outwardly from the first region.

3. The clot retrieving device of Clause 1 or Clause 2 wherein, in thesecond configuration, the second portion of the cover has a third regionextending proximally from the second region.

4. The clot retrieving device of Clause 3 wherein, in the secondconfiguration, the second portion of the cover has a fourth region thatextends distally and radially outwardly from the third region, whereinthe third region and the fourth region meet at a proximal folded edge.

5. The clot retrieving device of any one of Clauses 1-4 wherein, in thesecond configuration, the first and second regions of the second portiontogether define a channel extending therethrough.

6. The clot retrieving device of Clause 5 wherein, in the secondconfiguration, the first portion of the cover defines anaxially-extending cavity that is continuous with the channel of thesecond portion.

7. The clot retrieving device of Clause 5 or Clause 6 wherein a diameterof the channel decreases in a distal direction along the first regionand increases in a distal direction along the second region.

8. The clot retrieving device of any one of Clauses 1-7 wherein, whenthe cover is unconstrained in the first configuration, thecross-sectional area at the second portion of the cover is greater thanthe cross-sectional area at the first portion of the cover.

9. The clot retrieving device of any one of Clauses 1-8 wherein thecover is a braid comprising a plurality of interwoven filaments.

10. The clot retrieving device of Clause 9 wherein at least some of theplurality of filaments comprise a superelastic material.

11. The clot retrieving device of Clause 9 wherein at least some of theplurality of filaments are drawn-filled tube (“DFT”) wires comprising aradiopaque core material surrounded by a superelastic material.

12. The clot retrieving device of any one of Clauses 1-11 wherein thecapture structure is a stent.

13. The clot retrieving device of Clause 12 wherein the stent is a cuttube.

14. A clot retrieving device, comprising:

-   -   an elongated shaft having a distal region;    -   a capture structure having a proximal portion coupled to the        distal region of the elongated shaft and a distal portion having        a distal terminus; and    -   a cover coupled to the distal region of the elongated shaft, the        cover having a first portion and a second portion extending from        the first portion, wherein the cover has (a) a first        configuration in which the second portion of the cover extends        proximally from the first portion, and (b) a second        configuration in which the capture structure is at least        partially ensheathed within the first portion of the cover and        the second portion extends distally from the first portion, and        wherein, in the second configuration, the second portion has:        -   a neck portion distal to the capture structure, the neck            portion having a cross-sectional area that decreases then            increases in a distal direction,        -   a broad portion that curves radially outwardly and            proximally from a distal region of the neck portion, and        -   a channel extending through the neck portion that terminates            at an opening at a distal face of the cover.

15. The clot retrieving device of Clause 14 wherein, in the secondconfiguration, the broad portion of the second portion curvescircumferentially radially outwardly and proximally from the distalregion of the neck portion.

16. The clot retrieving device of Clause 14 or Clause 15 wherein, in thesecond configuration, the second portion of the cover has an invertedportion that extends distally and radially outwardly from the broadportion, wherein the broad portion and the inverted portion meet at acurved edge.

17. The clot retrieving device of any one of Clauses 14-16 wherein, inthe second configuration, a length of the neck portion and a length ofthe broad portion define the distal face of the cover.

18. The clot retrieving device of any one of Clauses 14-17 wherein, inthe second configuration, the broad portion surrounds and is spacedapart from at least a portion of the length of the neck portion.

19. The clot retrieving device of any one of Clauses 14-18 wherein, inthe second configuration, a cross-sectional area of the broad portion isgreater than the cross-sectional area of the first portion of the cover.

20. The clot retrieving device of any one of Clauses 14-19 wherein, whenthe cover is unconstrained in the first configuration, thecross-sectional area at the second portion of the cover is greater thanthe cross-sectional area at the first portion of the cover.

21. The clot retrieving device of any one of Clauses 14-20 wherein inthe second configuration the cover is inverted relative to the firstconfiguration.

22. The clot retrieving device of any one of Clauses 14-21 wherein thecover is a braid comprising a plurality of interwoven filaments.

23. The clot retrieving device of Clause 22 wherein at least some of theplurality of filaments comprise a superelastic material.

24. The clot retrieving device of Clause 22 wherein at least some of theplurality of filaments are drawn-filled tube (“DFT”) wires comprising aradiopaque core material surrounded by a superelastic material.

25. The clot retrieving device of any one of Clauses 14-24 wherein thecapture structure is a stent.

26. The clot retrieving device of Clause 25 wherein the stent is a cuttube.

27. A device for removing material from a vessel, comprising:

-   -   an elongated shaft configured to position and advance a capture        structure and a cover within the vessel,    -   the capture structure configured to interlock with a portion of        the material, and the cover configured to invert when advanced        proximally and,    -   when inverted, a first portion of the cover is configured to        ensheath the capture structure and a second portion of the cover        is configured to extend distally from the first portion, taper        radially inward from a distal terminus of the capture structure        to a narrow portion, and then curve radially outward from the        narrow portion.

28. The clot retrieving device of Clause 27 wherein, when inverted, thesecond portion of the cover is configured to curve circumferentiallyradially outward from the narrow portion.

29. The clot retrieving device of Clause 27 or Clause 28 wherein thedevice is configured to be removed from the vessel and the invertedcover is configured to evert after removal.

30. The clot retrieving device of Clause 29 wherein the device havingthe everted cover is configured to be re-positioned within the vessel orpositioned within a different vessel.

31. A method for using a clot retrieval device to retrieve clot materialfrom a blood vessel of a patient, the clot retrieval device including acapture structure and a cover having a first portion and a secondportion, the method comprising:

-   -   expanding the clot retrieval device within the blood vessel        lumen into a first configuration such that the second portion of        the cover extends proximally from the first portion of the cover        and the second portion of the cover contacts an interior surface        of the vessel wall;    -   moving the capture structure proximally relative to the cover to        transform the clot retrieval device from the first configuration        into a second configuration in which (a) the first portion of        the cover surrounds the capture structure, and (b) the second        portion extends distally from the first portion, the second        portion tapering radially inward distal to a distal terminus of        the capture structure to a narrow region, and then curves        radially outwardly from the narrow region to form a wide region;        and    -   retaining at least a portion of the clot material within the        cover and removing the clot material and clot retrieval device        from the patient with the clot retrieval device in the second        configuration.

32. The method of Clause 31 wherein the wide region includes:

-   -   a first portion extending distally and radially outwardly from a        distal terminus of the narrow region, and    -   a second portion extending proximally from a distal terminus of        the first portion of the wide region.

33. The method of Clause 32 wherein the wide region further includes athird portion extending distally and radially outwardly from a distalterminus of the wide region, wherein the second portion of the wideregion and the third portion of the wide region meet at a proximal edgeof the wide region.

34. The method of any one of Clauses 31-33 wherein the clot retrievaldevice is constrained within a delivery sheath during delivery of theclot retrieval device to the clot material, and wherein expanding theclot retrieval device includes withdrawing the delivery sheathproximally beyond the cover.

35. The method of any one of Clauses 31-34, further comprising invertingthe first portion of the cover while the second portion of the coverremains in contact with the vessel wall.

36. The method of any one of Clauses 31-35 wherein, when the clotretrieval device is positioned in the blood vessel in the firstconfiguration, the second portion of the cover exerts a greater radiallyoutward force on the vessel wall than the first portion.

37. The method of any one of Clauses 31-36 wherein expanding the clotretrieval device includes expanding the capture structure distal of theclot material.

38. A device for retrieving clot material from a blood vessel, thedevice comprising:

-   -   an elongated member having a distal region configured to be        intravascularly positioned at or near the clot material within        the blood vessel; and    -   a cover having a proximal portion, an intermediate portion, and        a distal portion, the cover slideably coupled to the distal        region of the elongated member at a connector, the cover having        an inner layer and an outer layer continuous with the inner        layer at the distal terminus of the cover, wherein the proximal        end portions of each of the inner layer and the outer layer are        fixed relative to one another at the connector, and wherein, at        least when the cover is in an expanded, relaxed state:    -   the inner layer has (a) a first cross-sectional dimension at the        proximal portion of the cover, (b) a distally increasing        cross-sectional dimension along the intermediate portion of the        cover, and (c) a second cross-sectional dimension at the distal        portion of the cover, wherein the second cross-sectional        dimension is greater than the first cross-sectional dimension,        and    -   the outer layer has a cross-sectional dimension that is        generally constant along the distal portion and the intermediate        portion of the cover.

39. The device of Clause 38 wherein the cross-sectional dimension of theouter layer along the distal and intermediate portions of the cover isgreater than an inner diameter of the portion of the blood vesseladjacent to the clot material such that, when the cover is expandedwithin the blood vessel lumen, the outer layer exerts a radially outwardforce on the blood vessel wall along at least the distal andintermediate portions of the cover.

40. The device of Clause 38 or Clause 39 wherein, at least when thecover is in an expanded, relaxed state, the outer layer along theproximal portion of the cover has a distal region and a proximal regionextending proximally from the distal region to the connector, andwherein (a) the distal region has a generally constant cross-sectionaldimension, and (b) a cross-sectional dimension of the proximal regiondecreases in a proximal direction.

41. The device of Clause 40 wherein, at least when the cover is in anexpanded, relaxed state, the cross-sectional dimension of the distalregion of the outer layer is substantially the same as thecross-sectional dimension along the distal and intermediate portions ofthe cover.

42. The device of any one of Clauses 38-41 wherein, at least when thecover is in an expanded, relaxed state, the first cross-sectionaldimension of the inner layer is generally constant along the proximalportion of the cover.

43. The device of any one of Clauses 38-42 wherein, at least when thecover is in an expanded, relaxed state, the second cross-sectionaldimension of the inner layer is generally constant along the distalportion of the cover.

44. The device of any one of Clauses 38-43 wherein, at least when thecover is in an expanded, relaxed state:

-   -   the first cross-sectional dimension of the inner layer is        generally constant along the proximal portion of the cover, and    -   the second cross-sectional dimension of the inner layer is        generally constant along the distal portion of the cover.

45. The device of any one of Clauses 38-44 wherein the distal terminusof the cover defines an opening configured to receive a capturestructure therethrough, and wherein the cover includes a cavityextending proximally from the opening to the connector.

46. The device of Clause 45 wherein the intermediate portion of theinner layer is convex towards the cavity.

47. The device of Clause 45 wherein the intermediate portion of theinner layer has a distal region that is concave towards the cavity, anda proximal region that is convex towards the cavity.

48. The device of any one of Clauses 38-47 wherein the distal terminusof the cover is a folded edge.

49. The device of any one of Clauses 38-48 wherein the cover is aninverted tubular braid.

50. The device of any one of Clauses 38-49 wherein the elongated memberis a solid wire.

51. The device of any one of Clauses 38-50, wherein, when the capturestructure is received in the cover, a first portion of the inner layeris displaced radially outward to accommodate the capture structure, anda second portion of the inner layer, located distal of the firstportion, remains collapsed radially inward to form at least a partialclosure distal of the capture structure.

52. A system for retrieving clot material from a blood vessel, thesystem comprising:

-   -   an elongated member having a distal region configured to be        intravascularly positioned at or near the clot material within        the blood vessel;    -   a capture structure having a proximal portion coupled to the        distal region of the elongated member at a first connector; and    -   a cover coupled to the distal region of the elongated member at        a second connector, the second connector proximal of the first        connector along the elongated member, wherein the cover has a        first portion extending proximally from the distal terminus, a        second portion extending proximally from first portion, and a        third portion extending proximally from the second portion to        the second connector,    -   wherein the cover has an inner layer and an outer layer        continuous with the inner layer at the distal terminus of the        cover, each of the inner layer and the outer layer having        proximal ends fixed at the second connector, and wherein, at        least when the cover is in an expanded, relaxed state:        -   the inner layer has a funnel-shaped region along the first            portion of the cover and a neck region extending along the            second and third portions of the cover, and        -   the outer layer has a generally cylindrical shape along the            first and second portions of the cover, and a decreasing            cross-sectional dimension along the third portion of the            cover.

53. The system of Clause 52 wherein the funnel-shaped region of thecover has a distal portion with a generally constant cross-sectionaldimension and a tapered proximal portion.

54. The system of Clause 52 or Clause 53 wherein, at least when thecover is in an expanded, relaxed state, the distal terminus of the coversurrounds an opening configured to receive the capture structuretherethrough.

55. The system of Clause 54 wherein the inner layer surrounds a cavityextending from the opening to the third portion of the cover.

56. The system of any one of Clauses 52-55 wherein, as the capturestructure is moved proximally along the neck region of the inner layerwhile the cover is expanded within the blood vessel such that the outerlayer contacts with the blood vessel wall, a distance between the innerlayer and the outer layer decreases along the portion of the coveraxially aligned with the capture structure.

57. The system of any one of Clauses 52-56 wherein the cover is aninverted tubular braid.

58. The system of any one of Clauses 52-57 wherein the cover is a meshand the capture structure is a stent formed of a cut tube.

59. The system of any one of Clauses 52-58, wherein, when the capturestructure is received in the cover, a first portion of the inner layeris displaced radially outward to accommodate the capture structure, anda second portion of the inner layer, located distal of the firstportion, remains collapsed radially inward to form at least a partialclosure distal of the capture structure.

60. A system for retrieving clot material from a blood vessel, thesystem comprising:

-   -   an elongated member having a distal region configured to be        intravascularly positioned at or near the clot material within        the blood vessel;    -   a capture structure having a proximal portion coupled to the        distal region of the elongated member; and    -   a dual-layer cover coupled to the distal region of the elongated        member at a location proximal of the capture structure, wherein        the cover has a radially expansile outer layer that tends to        self-expand toward an inner wall of the blood vessel, and an        inner layer that tends to collapse inward toward the elongated        member such that the inner layer is spaced radially inward from        the outer layer; and    -   the cover being slidable on the elongated member so that the        capture structure can be received in the cover.

61. The system of Clause 60, wherein, when the capture structure isreceived in the cover, a first portion of the inner layer is displacedradially outward to accommodate the capture structure, and a secondportion of the inner layer, located distal of the first portion, remainscollapsed radially inward to form at least a partial closure distal ofthe capture structure.

62. The system of Clause 60 or 61, wherein the cover has a closedproximal end.

63. The system of any one of Clauses 60-62, wherein a distalmost portionof the inner layer is not collapsed radially inward, so as to form anenlarged distal opening of the cover.

64. The system of any one of Clauses 60-63, wherein the distalmostportion of the inner layer extends proximally in at least partialcontact with a radially adjacent portion of the outer layer.

65. The system of any one of Clauses 60-64, wherein at least the distalregion of the elongated member comprises a wire.

66. The system of any one of Clauses 60-65, wherein at least the distalregion of the elongated member comprises a stent retriever.

67. The system of any one of Clauses 60-66, wherein a distal terminus ofthe cover is a folded edge.

68. The system of any one of Clauses 60-67, wherein the cover is aninverted tubular braid and the capture structure is a stent formed of acut tube.

69. The system of any of Clauses 60-68, wherein the cover is coupled tothe elongated member at a connector, and wherein the cover has aproximal portion, an intermediate portion, and a distal portion, andwherein, at least when the cover is in an expanded, relaxed state:

-   -   the inner layer has (a) a first cross-sectional dimension at the        proximal portion of the cover, (b) a distally increasing        cross-sectional dimension along the intermediate portion of the        cover, and (c) a second cross-sectional dimension at the distal        portion of the cover, wherein the second cross-sectional        dimension is greater than the first cross-sectional dimension,        and    -   the outer layer has a cross-sectional dimension that is        generally constant along the distal portion and the intermediate        portion of the cover.

70. A device for retrieving clot material from a blood vessel lumen, thedevice comprising:

-   -   an elongated shaft having a distal zone;    -   a capture structure having a proximal region coupled to the        distal zone of the elongated shaft;    -   a cover having a first portion coupled to the distal zone of the        elongated shaft and a free second portion, the cover having a        first position in which the second portion extends proximally        from the first portion, and a second position inverted relative        to the first position in which the second portion extends        distally from the first portion such that the cover at least        partially surrounds the capture structure; and    -   a connector coupled to the elongated shaft proximal of the        capture structure, the connector including an inner band and an        outer band, wherein (a) the inner band at least partially        surrounds a portion of the distal zone of the elongated        shaft, (b) the outer band at least partially surrounds the inner        band, and (c) the first portion of the cover is secured between        the inner band and the outer band.

71. The device of Clause 70 wherein the connector is coupled to thedistal zone of the elongated shaft by a crimp and/or a binding agent.

72. The device of Clause 70 wherein the connector is configured to movewith respect to the elongated shaft.

73. The device of any one of Clauses 70-72 wherein the connector is afirst connector and the device further comprises a second connector atleast partially surrounding the proximal region of the capturestructure, and wherein the inner band of the first connector has a firstinner diameter and the second connector has a second inner diametergreater than or equal to the first inner diameter of the inner band.

74. The device of any one of Clauses 70-73, wherein the connector iscrimped to the first portion of the cover.

75. The device of any one of Clauses 72-74, further comprising a stopfixed to the elongated shaft proximal of the connector.

76. The device of Clause 75 wherein the stop includes a coil attached tothe elongated shaft.

77. The device of any one of Clauses 70-76 wherein the connector is afirst connector, the device further comprising a second connector,wherein the second connector and the inner band and/or the outer bandare composed of a radiopaque material.

78. The device of any one of Clauses 70-77 wherein the inner band and/orthe outer band are composed of a radiopaque material.

79. The device of any one of Clauses 70-78 wherein the cover is composedof a plurality of drawn-filled tube (“DFT”) wires, and at least aportion of the outer band comprises platinum.

80. The device of any one of Clauses 70-79 wherein at least a portion ofthe cover comprises a superelastic material.

81. The device of any one of Clauses 70-80 wherein the inner and outerbands have generally the same length.

82. The device of any one of Clauses 70-81 wherein a distal terminus ofthe inner band and a distal terminus of the outer band are at leastgenerally aligned along a plane approximately normal to the elongatedshaft.

83. The device of any one of Clauses 70-82 wherein a proximal terminusof the inner band and a proximal terminus of the outer band are at leastgenerally aligned along a plane approximately normal to the elongatedshaft.

84. The device of any one of Clauses 70-83 wherein the cover includes aplurality of interwoven wires, and a portion of the wires protrudeproximally from a proximal terminus of the outer band, and wherein thedevice further comprises a jacket over the proximal terminus of theouter band and the protruding portion of the wires.

85. The device of Clause 84 wherein the jacket further extends over aportion of the elongated shaft proximal of the proximal terminus of theouter band.

86. The device of any one of Clauses 70-85 wherein the inner band andthe outer band each include a proximal terminus, and the proximalterminus of the inner band extends proximally beyond the proximalterminus of the outer band, the device further comprising a jacket overthe proximal terminus of the outer band and a portion of the inner bandthat extends proximal of the proximal terminus of the outer band.

87. The device of any one of Clauses 70-86 wherein the capture structureis a stent and the cover is a braid.

88. A device for retrieving clot material from a blood vessel lumen, thedevice comprising:

-   -   an interventional element having an elongated proximal region;    -   a manipulation member having a distal zone, wherein the proximal        region of the interventional element is coupled to the distal        zone of the manipulation member;    -   a cover having a first portion coupled to the distal zone of the        manipulation member and a free second portion, the cover having        a first position in which the second portion extends proximally        from the first portion, and a second position inverted relative        to the first position in which the second portion extends        distally from the first portion such that the cover at least        partially surrounds the interventional element;    -   an inner band proximal to the interventional element and at        least partially surrounding a portion of the distal zone of the        manipulation member; and    -   an outer band at least partially surrounding the inner band,        wherein the first portion of the cover is secured between the        inner band and the outer band.

89. The device of Clause 88 wherein the inner band, the cover and theouter band are coupled to the distal zone of the manipulation member bya crimp and/or a binding agent.

90. The device of Clause 88 wherein the inner band and the outer bandare configured to move with respect to the manipulation member.

91. The device of any one of Clauses 88-90 wherein the inner band andthe outer band are crimped to the first portion of the cover.

92. The device of any one of Clauses 88-91, further comprising a stopfixed to the manipulation member and proximal of the inner band, whereinthe stop has an inner diameter greater than the inner diameter of theinner band.

93. The device of any one of Clauses 88-92, further comprising aconnector at least partially surrounding the proximal region of theinterventional element and a portion of the distal zone of themanipulation member, wherein at least a portion of the cover comprises asuperelastic material, and the connector and/or the outer band arecomposed of a radiopaque material.

94. The device of any one of Clauses 88-93 wherein a proximal terminusof the inner band and a proximal terminus of the outer band aregenerally aligned along a plane approximately normal to the manipulationmember.

95. A method for retrieving clot material from a treatment site within ablood vessel lumen, the method comprising:

-   -   providing a clot retrieving device including an elongated shaft        having a distal zone and a retrieval assembly at the distal        zone, the retrieval assembly having:    -   a capture structure with a proximal region coupled to the distal        zone of the elongated shaft,    -   a cover having a first portion coupled to the distal zone of the        elongated shaft and a free second portion, the cover having a        first position in which the second portion extends proximally        from the first portion, and a second position in which the        second portion extends distally from the first portion such that        the cover at least partially surrounds the capture structure,        and    -   a connector coupled to the elongated shaft proximal of the        capture structure, the connector including an inner band and an        outer band, wherein (a) the inner band at least partially        surrounds the distal zone of the elongated shaft, (b) the outer        band at least partially surrounds the inner band, and (c) the        first portion of the cover is secured between the inner band and        the outer band;    -   intravascularly advancing the clot retrieving device within a        delivery catheter to the treatment site such that the retrieval        assembly is positioned proximate the clot material at the        treatment site;    -   deploying the retrieval assembly within the blood vessel lumen        such that the capture structure expands at the clot material and        the cover is in the first position; and    -   withdrawing the retrieval assembly proximally through the        delivery catheter to remove the clot material from the treatment        site.

96. The device of Clause 95 wherein the connector is coupled to thedistal zone of the elongated shaft by a crimp and/or a binding agent.

97. The device of Clause 95, further comprising moving the connectoraxially relative to the elongated shaft.

98. The device of any one of Clauses 95-97 wherein the retrievalassembly further includes a stop proximal to the connector, and whereinthe stop includes a coil attached to the elongated shaft.

99. The device of any one of Clauses 95-98 wherein deploying theretrieval assembly includes inverting the cover from the first positionto the second position.

100. A device for retrieving clot material from a blood vessel lumen,the device comprising:

-   -   an elongated shaft having a distal zone;    -   a capture structure having a proximal region coupled to the        distal zone of the elongated shaft;    -   a cover having a first end portion coupled to the distal zone of        the elongated shaft and a free second end portion, the cover        having a first position in which the second end portion extends        proximally from the first end portion, and a second position in        which the second end portion extends distally from the first end        portion such that the cover at least partially surrounds the        capture structure and is inverted relative to the first        position;    -   a connector coupled to the distal zone of elongated shaft, the        connector including an inner band and an outer band, wherein (a)        the inner band at least partially surrounds the distal zone of        the elongated shaft and a portion of the proximal region of the        capture structure, (b) the outer band at least partially        surrounds the inner band, and (c) the first end portion of the        cover is secured between the inner band and the outer band.

101. The device of Clause 100, further comprising a jacket material overa proximal terminus of the inner band and a portion of the elongatedshaft proximal of the proximal terminus of the inner band.

102. The device of Clause 101 wherein the jacket material is an innerjacket material, the device further comprising an outer jacket materialover a proximal terminus of the outer band and at least a portion of theinner jacket material proximal of the proximal terminus of the outerband.

103. The device of Clause 101 or Clause 102 wherein the jacket materialis an inner jacket material, the device further comprising an outerjacket material over a proximal terminus of the outer band and at leasta portion of the elongated shaft proximal of the proximal terminus ofthe outer band.

104. The device of any of Clauses 100-104, further comprising an innerjacket material and an outer jacket material, wherein the inner jacketmaterial is over a proximal terminus of the inner band and the outerjacket material is over a proximal terminus of the outer band.

105. The device of Clause 100 wherein the proximal region of the capturestructure, the connector, and the first end portion of the cover arecoupled to the distal zone of the elongated shaft by a crimp.

106. The device of any one of Clauses 100-105 wherein at least one ofthe inner band and the outer band is composed of a radiopaque material.

107. The device of any one of Clauses 100-106 wherein the cover iscomposed of a plurality of drawn-filled tube (“DFT”) wires, and at leasta portion of the outer band comprises platinum.

108. The device of any one of Clauses 100-107 wherein at least a portionof the cover comprises a superelastic material.

109. The device of any one of Clauses 100-108 wherein the inner andouter bands have generally the same length.

110. The device of any one of Clauses 100-109 wherein a distal terminusof the inner band and a distal terminus of the outer band are generallyaligned along a plane normal to the elongated shaft.

111. The device of any one of Clauses 100-110 wherein a proximalterminus of the inner band and a proximal terminus of the outer band aregenerally aligned along a plane normal to the elongated shaft.

112. The device of any of Clauses 100-111 wherein the proximal region ofthe capture structure, the connector, and the first end portion of thecover are coupled to the distal zone of the elongated shaft.

113. The device of any one of Clauses 100-112 wherein the cover includesa plurality of interwoven wires, and a portion of the wires protrudeproximally from a proximal terminus of the outer band, and wherein thedevice further comprises a jacket material over the proximal terminus ofthe outer band and the protruding portion of the wires.

114. The device of any one of Clauses 100-113 wherein the inner band andthe outer band each include a proximal terminus, and the proximalterminus of the inner band extends proximally beyond the proximalterminus of the outer band, and wherein the device further comprises ajacket material over the proximal terminus of the outer band and aportion of the inner band proximal of the proximal terminus of the outerband.

115. The device of any one of Clauses 100-114 wherein the capturestructure is a stent and the cover is a braid.

116. A device for retrieving clot material from a blood vessel lumen,the device comprising:

-   -   an interventional element having an elongated proximal region        and an opening extending laterally through the proximal region;    -   a manipulation member having a distal zone and a coupling        element at the distal zone, wherein at least a portion of the        coupling element extends through the opening at the proximal        region of the interventional element;    -   a cover having a first end portion coupled to the distal zone of        the manipulation member and a free second end portion, wherein        the cover has a first position in which the second end portion        extends proximally from the first end portion, and a second        position in which the second end portion extends distally from        the first end portion such that the cover at least partially        surrounds the interventional element and is inverted relative to        the first position.    -   an inner band at least partially surrounding the distal zone of        the manipulation member and a portion of the proximal region of        the interventional element; and    -   an outer band at least partially surrounding the inner band,        wherein the first end portion of the cover is secured between        the inner band and the outer band.

117. The device of Clause 116, further comprising a jacket material overa proximal terminus of the inner band and at least a portion of theelongated shaft proximal of the proximal terminus of the inner band.

118. The device of Clause 117 wherein the jacket material is an innerjacket material, the device further comprising an outer jacket materialover a proximal terminus of the outer band and at least a portion of theinner jacket material proximal of the proximal terminus of the outerband.

119. The device of Clause 116, further comprising an inner jacketmaterial and an outer jacket material, wherein the inner jacket materialcovers a proximal terminus of the inner band and the outer jacketmaterial covers a proximal terminus of the outer band.

120. The device of any of Clauses 116-119 wherein the proximal region ofthe interventional element, the inner band, the outer band and the firstend portion of the cover are coupled to the distal zone of the elongatedshaft by a crimp.

121. The device of any one of Clauses 116-120 wherein at least a portionof the distal zone of the manipulation member is bent.

122. The device of any one of Clauses 116-121 wherein at least one ofthe inner band and the outer band is composed of a radiopaque material,and the cover is composed of a plurality of DFT wires.

123. The device of any one of Clauses 116-122 wherein the cover includesa plurality of interwoven wires, and a portion of the wires protrudeproximally from a proximal terminus of the outer band, and wherein thedevice further comprises an inner jacket material and an outer jacketmaterial, the inner jacket material covering a proximal terminus of theinner band and the outer jacket material covering a proximal terminus ofthe outer band and the portion of protruding wires.

124. A method for retrieving clot material from a treatment site withina blood vessel lumen, the method comprising:

-   -   providing a clot retrieving device including an elongated shaft        having a distal zone and a retrieval assembly at the distal        zone, the retrieval assembly having:    -   a capture structure with a proximal region coupled to the distal        zone of the elongated shaft,    -   a cover having a first end portion coupled to the distal zone of        the elongated shaft and a free second end portion, the cover        having a first position in which the second end portion extends        proximally from the first end portion, and a second position in        which the second end portion extends distally from the first end        portion such that the cover at least partially surrounds the        capture structure and is inverted relative to the first        position, and    -   a connector coupled to the distal zone of elongated shaft, the        connector including an inner band and an outer band, wherein (a)        the inner band at least partially surrounds the distal zone of        the elongated shaft and the proximal region of the capture        structure, (b) the outer band at least partially surrounds the        inner band, and (c) the first end portion of the cover is        secured between the inner band and the outer band;    -   intravascularly advancing the clot retrieving device within a        delivery catheter to the treatment site such that the retrieval        assembly is positioned proximate the clot material at the        treatment site;    -   deploying the retrieval assembly within the blood vessel lumen        such that the retrieval assembly expands to the first position;        and    -   withdrawing the retrieval assembly proximally through the        delivery catheter to remove clot material from the treatment        site.

125. The method of Clause 124, further comprising an inner jacketmaterial over a proximal terminus of the inner band, and an outer jacketmaterial over a proximal terminus of the outer band.

126. The method of Clause 124 or Clause 125 wherein the proximal regionof the capture structure, the connector, and the first end portion ofthe cover are coupled to the distal zone of the elongated shaft by acrimp.

127. The method of any one of Clauses 124-126 wherein the cover includesa plurality of interwoven wires, and a portion of the wires protrudeproximally from a proximal terminus of the outer band, and wherein thedevice further comprises a jacket material at least partially over theproximal terminus of the outer band and the protruding portion of thewires.

128. The method of any one of Clauses 124-127 wherein at least one ofthe inner band and the outer band is composed of a radiopaque material,and the cover is composed of a plurality of DFT wires.

129. The method of any one of Clauses 124-128 wherein the inner band andthe outer band each include a proximal terminus, and the proximalterminus of the inner band extends proximally beyond the proximalterminus of the outer band, and wherein the device further comprises ajacket material at least partially over the proximal terminus of theouter band and the inner band proximally adjacent the proximal terminusof the outer band.

130. A device for retrieving clot material from a blood vessel lumen,the device comprising:

-   -   an elongated shaft having a distal zone;    -   a capture structure having a proximal region coupled to the        distal zone of the elongated shaft;    -   a cover including a plurality of filaments, the cover having a        first portion coupled to the distal zone of the elongated shaft        and a free second portion, the cover having a first position in        which the second portion extends proximally from the first        portion, and a second position inverted relative to the first        position in which the second portion extends distally from the        first portion such that the cover at least partially surrounds        the capture structure;    -   a connector coupling the first portion of the cover to the        distal zone of the elongated shaft, wherein at least a portion        of the filaments protrude proximally from a proximal terminus of        the connector; and    -   a jacket at least partially over the proximal terminus of the        connector and the protruding portion of the filaments, wherein        the jacket prevents direct contact between the cover and the        protruding portions of the filaments as the cover moves from the        first position to the second position.

131. The device of Clause 130 wherein the cover is a braid, and thecapture structure is a stent.

132. The device of Clause 130 or Clause 131 wherein the jacket includesa polymer.

133. The device of any one of Clauses 130-132 wherein the jacketincludes a fluoropolymer.

134. The device of any one of Clauses 130-133 wherein at least a portionof the jacket comprises polytetrafluoroethylene (“PTFE”).

135. The device of any one of Clauses 130-134 wherein the jacketincludes a heat-shrinkable material.

136. The device of any one of Clauses 130-135 wherein the jacket is atleast partially over a portion of the elongated shaft proximal of theproximal terminus of the connector.

137. The device of any one of Clauses 130-136 wherein the inner band atleast partially surrounds the proximal region of the capture structure.

138. The device of any one of Clauses 130 wherein the connector is afirst connector, and the device further comprises a second connectordistal of the first connector along the elongated shaft, wherein thesecond connector at least partially surrounds the proximal region of thecapture structure and the distal zone of the elongated shaft.

139. The device of any one of Clauses 130-138 wherein the firstconnector is configured to move with respect to the elongated shaft.

140. The device of any one of Clauses 130-139, further comprising a stopfixed to the elongated shaft proximal of the first connector.

141. The device of any one of Clauses 130-140 wherein the connectorincludes an inner band and an outer band, and wherein:

-   -   the inner band at least partially surrounds a portion of the        distal zone of the elongated shaft,    -   the outer band at least partially surrounds the inner band, and    -   the first portion of the cover is secured between the inner band        and the outer band.

142. The device of Clause 141 wherein the portion of the elongated shaftis a first portion, and the device further comprises a buffer materialpositioned over a second portion of the elongated shaft proximal of theproximal terminus of the inner band.

143. The device of Clause 142 wherein the buffer material is a coil.

144. A device for retrieving clot material from a blood vessel lumen,the device comprising:

-   -   an interventional element;    -   a manipulation member having a distal zone;    -   a cover having a first portion coupled to the distal zone of the        manipulation member and a free second portion, the cover having        a first position in which the second portion extends proximally        from the first portion, and a second position inverted relative        to the first position in which the second portion extends        distally from the first portion such that the cover surrounds at        least a portion of the interventional element;    -   a connector coupling the first portion of the cover to the        distal zone of the manipulation member, wherein at least a        portion of the cover extends proximally from a proximal terminus        of the connector; and    -   a jacket extending from the proximal terminus of the connector        and covering the extending portion of the cover, thereby        preventing the extending portion of the cover from engaging the        remaining portion of the cover as the cover moves from the first        position to the second position.

145. The device of Clause 144 wherein the interventional elementincludes a proximal region at least partially surrounded by theconnector.

146. The device of Clause 145 or Clause 146 wherein the connectorincludes an inner band and an outer band, and wherein the jacket is anouter sleeve, the device further comprising an inner sleeve over aproximal terminus of the inner band and a portion of the manipulationmember proximal of the proximal terminus of the inner band.

147. The device of any one of Clauses 144-146 wherein the connector is afirst connector, the device further comprising a second connector atleast partially surrounding the proximal region of the interventionalelement and the portion of the distal zone of the manipulation member.

148. The device of any one of Clauses 144-147 wherein the connectorincludes an inner band and an outer band, and wherein the inner band isproximal of the proximal region of the interventional element and atleast partially surrounds a portion of the distal zone of themanipulation member, and the outer band at least partially surrounds theinner band.

149. The device of Clause 146 or Clause 148 wherein a proximal terminusof the inner band extends proximally beyond a proximal terminus of theouter band, and wherein the jacket is at least partially over the innerband proximal of the proximal terminus of the outer band.

150. The device of any one of Clauses 144, 145, 147, 148 or 149 whereinthe inner band and the outer band are configured to move with respect tothe manipulation member.

151. The device of any one of Clauses 144-150, further comprising a stopfixed to the manipulation member proximal of the connector.

152. The device of any one of Clauses 144-151 wherein the jacket is aheat-shrinkable material.

153. The device of any one of Clauses 144-152 wherein at least a portionof the heat-shrinkable material is composed of a fluoropolymer.

154. The device of any one of Clauses 144-151 wherein:

-   -   the interventional element includes an elongated proximal region        and an opening extending laterally through the proximal region,        and    -   the manipulation member includes a coupling element at the        distal zone of the manipulation member, wherein at least a        portion of the coupling element extends through the opening of        the interventional element.

155. A method for retrieving clot material from a treatment site withina blood vessel lumen, the method comprising:

-   -   providing a clot retrieving device including an elongated shaft        having a distal zone and a retrieval assembly at the distal        zone, the retrieval assembly having:    -   a capture structure with a proximal region coupled to the distal        zone of the elongated shaft,    -   a cover having a plurality of filaments, a first portion coupled        to the distal zone of the elongated shaft and a free second        portion, the cover having a first position in which the second        portion extends proximally from the first portion, and a second        position inverted relative to the first position in which the        second portion extends distally from the first portion such that        the cover at least partially surrounds the capture structure,    -   a connector coupling the first portion of the cover to the        distal zone of the elongated shaft, wherein at least a portion        of the filaments protrude proximally from a proximal terminus of        the connector, and    -   a jacket at least partially over the proximal terminus of the        connector and the protruding portion of the filaments;    -   intravascularly advancing the clot retrieving device within a        delivery catheter to the treatment site such that the retrieval        assembly is positioned proximate the clot material at the        treatment site;    -   deploying the retrieval assembly within the blood vessel lumen        such that the retrieval assembly expands to the first position;        and    -   withdrawing the retrieval assembly proximally through the        delivery catheter to remove clot material from the treatment        site.

156. The method of Clause 155 wherein the connector at least partiallysurrounds the proximal region of the capture structure.

157. The method of Clause 155 wherein the connector is a first connectorproximal of the proximal region of the capture structure, and the devicefurther comprises a second connector at least partially surrounding theproximal region of the capture structure.

158. The method of any one of Clauses 155-157 wherein the jacket is atleast partially over a portion of the elongated shaft proximal of theproximal terminus of the connector.

159. The method of any one of Clauses 155-158 wherein the connectorincludes an inner band and an outer band, wherein:

-   -   the inner band at least partially surrounds a portion of the        distal zone of the elongated shaft,    -   the outer band at least partially surrounds the inner band, and    -   the first portion of the cover is secured between the inner band        and the outer band.

160. The method of any one of Clauses 155-159 wherein the jacket is aheat-shrinkable material composed of a fluoropolymer.

Additional features and advantages of the subject technology aredescribed below, and in part will be apparent from the description, ormay be learned by practice of the subject technology. The advantages ofthe subject technology will be realized and attained by the structureparticularly pointed out in the written description and claims hereof aswell as the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present technology can be better understood withreference to the following drawings. The components in the drawings arenot necessarily to scale. Instead, emphasis is placed on illustratingclearly the principles of the present disclosure.

FIG. 1A is a side view of a distal portion of a clot retrieval deviceshown with a retrieval assembly in a first configuration in accordancewith the present technology.

FIG. 1B is a side view of the distal portion of the clot retrievaldevice of FIG. 1A, shown with the retrieval assembly shown in a second,everted configuration.

FIGS. 2A-2G illustrate a method of removing clot material from a bloodvessel lumen using the clot retrieval device shown in FIGS. 1A and 1B.

FIG. 3A is a side view of a distal portion of a clot retrieval deviceshown with a retrieval assembly shown in a first configuration inaccordance with embodiments of the present technology.

FIG. 3B is a side view of the distal portion of the clot retrievaldevice of FIG. 3A, shown with the retrieval assembly in a second,everted configuration.

FIGS. 3C and 3D are enlarged side and isometric views, respectively, ofa portion of the cover of FIGS. 3A and 3B in an everted configuration inaccordance with some embodiments of the present technology.

FIGS. 4A-4N are side views of different end regions of covers in a firstconfiguration in accordance with some embodiments of the presenttechnology.

FIGS. 5A and 5B illustrate a method of removing clot material from ablood vessel lumen using the clot retrieval device shown in FIGS. 3A and3B.

FIG. 6A is a side view of a distal portion of a clot retrieval device inaccordance with some embodiments of the present technology.

FIG. 6B is an enlarged view of a portion of the cover shown in FIG. 6A.

FIG. 7 is a side view of the clot retrieval device shown in FIG. 6Apositioned in a blood vessel in an expanded state.

FIGS. 8A-8C illustrate a method of removing clot material from a bloodvessel lumen using the clot retrieval device shown in FIG. 6A.

FIG. 9A is a cross-sectional side view of a distal portion of a clotretrieving device in accordance with some embodiments of the presenttechnology.

FIG. 9B is a cross-sectional isometric view of the distal portion of theclot retrieving device shown in FIG. 9A.

FIGS. 10 and 11 are cross-sectional side views of the distal portion ofa clot retrieving device in accordance with some embodiments of thepresent technology.

FIG. 12A is a cross-sectional side view of a distal portion of a clotretrieving device in accordance with some embodiments of the presenttechnology.

FIG. 12B is a cross-sectional isometric view of the distal portion ofthe clot retrieving device shown in FIG. 12A.

FIGS. 13-15 are cross-sectional side views of the distal portion of aclot retrieving device in accordance with some embodiments of thepresent technology.

DETAILED DESCRIPTION

The present technology provides devices, systems, and methods forremoving clot material from a blood vessel lumen. Although many of theembodiments are described below with respect to devices, systems, andmethods for treating a cerebral or intracranial embolism, otherapplications and other embodiments in addition to those described hereinare within the scope of the technology. For example, the retrievaldevices of the present technology may be used to remove emboli from bodylumens other than blood vessels (e.g., the digestive tract, etc.) and/ormay be used to remove emboli from blood vessels outside of the brain(e.g., pulmonary blood vessels, blood vessels within the legs, etc.). Inaddition, the retrieval devices of the present technology may be used toremove luminal obstructions other than clot material (e.g., plaque,resected tissue, foreign material, etc.).

An overview of the retrieval devices of the present technology andassociated methods of use is described below under heading 1.0 withreference to FIGS. 1A-2G. Some embodiments of various subcomponents ofthe retrieval devices of the present technology are described belowunder headings 2.0 and 3.0. In particular, some embodiments of coversare described further under heading 2.0 with reference to FIGS. 3A-8C,and some embodiments of connection assemblies are described furtherunder heading 3.0 with reference to FIGS. 9A-15.

1.0 OVERVIEW

FIGS. 1A and 1B are side views of a distal portion of some embodimentsof a retrieval device or a clot retrieving device 10 (“device 10”)outside of a blood vessel in an expanded, relaxed (e.g., unconstrained)configuration in accordance with the present technology. The clotretrieving device 10 is shown in first and second configurations inFIGS. 1A and 1B, respectively. As shown in FIGS. 1A and 1B, the clotretrieving device 10 includes an elongated shaft 12 (“shaft 12”) and aretrieval assembly 14 coupled to a distal region of the elongated shaft12 via a connection assembly 300. The retrieval assembly 14 isconfigured to be intravascularly positioned at or adjacent clot materialwithin a blood vessel lumen and includes a capture structure 100 and aflexible cover 200. A portion of the cover is removed in FIGS. 1A and 1Bfor ease of viewing the capture structure 100. In some embodiments, thecapture structure 100 and the cover 200 are fixed to the elongated shaft12 at generally the same location, or the capture structure 100 andcover 200 may be coupled to the shaft 12 at different locations and/ormay be slidable with respect to the elongated shaft 12.

The capture structure 100 has a low-profile configuration (not shown)when constrained within a delivery catheter (e.g., a microcatheter) andan expanded configuration for securing and/or engaging clot material orother obstructions within a blood vessel lumen (e.g., a cerebral bloodvessel lumen) and/or for restoring blood flow within the blood vessel.The capture structure 100 has a proximal portion 100 a coupled to theshaft 12 and a distal portion 100 b. The capture structure 100 furtherincludes an open cell framework or body 108 (FIG. 1A) and a couplingregion 102 (FIG. 1A) extending proximally from the body 108. In someembodiments, for example as shown in FIGS. 1A and 1B, a distal portion100 b of the capture structure 100 can be generally tubular (e.g.,cylindrical), and the proximal portion 100 a of the capture structure100 tapers proximally to the coupling region 102. In some embodiments,the distal terminus of the distal portion 100 b coincides with a distalterminus 101 of the capture structure 100 and/or retrieval assembly 14.

Referring again to FIGS. 1A and 1B, in some embodiments the capturestructure 100 is a mesh structure formed of a superelastic material(e.g., Nitinol) or other resilient or self-expanding material configuredto self-expand when released from the delivery catheter. For example, insome embodiments the capture structure 100 may be a stent and/orstentriever, such as Medtronic's Solitaire™ Revascularization Device,Stryker Neurovascular's Trevo® ProVue™ Stentriever, or other suitabledevices. In other embodiments, the capture structure 100 may include aplurality of braided filaments. Examples of suitable capture structures100 include any of those disclosed in U.S. Pat. No. 7,300,458, filedNov. 5, 2007, U.S. Pat. No. 8,940,003, filed Nov. 22, 2010, U.S. Pat.No. 9,039,749, filed Oct. 1, 2010, and U.S. Pat. No. 8,066,757, filedDec. 28, 2010, each of which is incorporated by reference herein in itsentirety.

The cover 200 includes a first end portion 200 a coupled to the shaft 12via the connection assembly 300, a free second end portion 200 b, and acover wall 200 c extending between the first end portion 200 a and thesecond end portion 200 b. As used herein to describe the second endportion 200 b of the cover 200, the term “free” refers to a portion ofthe cover 200 that is not fixed to the elongated shaft 12 and may moveradially and/or longitudinally with respect to the shaft 12. The cover200 is flexible such that it is movable between a first position (FIG.1A) in which the free second end portion 200 b is proximal of the firstend portion 200 a and a second position (FIG. 1B) in which the cover 200is inverted over the capture structure 100 such that a distal terminus201 (FIG. 1B) of the cover 200 is at or distal to the distal terminus101 of the capture structure 100 and/or to the first end portion 200 a.As shown in FIG. 1A, when the cover 200 is in the first position in anexpanded, relaxed state, some embodiments of the cover 200 may have aleading edge 204 that overlaps the coupling region 102 of the capturestructure 100 but does not extend beyond the coupling region 102 tooverlap the body 108 of the capture structure 100. In some embodiments,the leading edge 204 of the cover 200 may also overlap all or a portionof the length of the body 108 when the cover 200 is in the firstposition. As shown in FIG. 1B, when the cover 200 is in the secondposition, the free second end portion 200 b is distal of the first endportion 200 a and distal of the distal terminus 101 of the capturestructure 100. As such, when in the second position, the cover wall 200c surrounds the capture structure 100.

The cover 200 can comprise a mesh and/or braid of a plurality of wires(e.g., filaments, threads, sutures, fibers or the like) that have beeninterwoven to form a structure having openings (e.g., a porous fabric).The mesh and/or braid can be composed of metals, polymers, composites,and/or biologic materials. Polymer materials can include Dacron,polyester, polypropylene, nylon, Teflon, polytetrafluoroethylene (PTFE),tetrafluoroethylene, polyethylene terephthalate, polyactic acid (PLA)silicone, polyurethane, polyethylene, polycarbonate, styrene, polyimide,PEBAX, Hytrel, polyvinyl chloride, high-density polyethylene,low-density polyethylene, polyether ether ketone (PEEK), rubber, latex,and/or other suitable polymers known in the art. Other materials knownin the art of elastic implants can also be used. Metal materials caninclude, but are not limited to, nickel-titanium alloys (e.g. Nitinol),platinum, cobalt-chromium alloys, stainless steel, tungsten or titanium.In certain embodiments, metal filaments may be highly polished and/orsurface treated to further improve their hemocompatibility. The cover200 can be constructed solely from metallic materials without theinclusion of any polymer materials, solely from polymer materialswithout the inclusion of any metallic materials, or a combination ofpolymer and metallic materials.

In some embodiments, some or all of the wires of the cover 200 aredrawn-filled tube (“DFT”) wires having a radiopaque core (e.g.,platinum, tantalum, gold, tungsten, etc.) surrounded by a superelasticmaterial (e.g., Nitinol, a cobalt-chromium alloy, etc.). The radiopaquecore may comprise about 5% to about 50% (e.g., 10%, 15%, 20%, 25%, 30%,35%, 40%, 45%) of the total-cross-sectional area of the individualwires. In some embodiments, the cover 200 may have 72-144 total wires(e.g., 72, 96 128, 144, etc.) Moreover, some or all of the wires mayhave a wire diameter of about 0.005 inches to about 0.015 inches (e.g.,0.008 inches, 0.01 inches, etc.). In some embodiments, all of the wireshave the same diameter, and in other embodiments some of the wires havedifferent diameters. Further details regarding cover embodiments inaccordance with the present technology are described below withreference to FIGS. 3A-8C.

FIGS. 2A-2G illustrate a method of removing clot material from the lumenof a blood vessel V using the clot retrieving device 10 of the presenttechnology. As shown in FIG. 2A, a guidewire 1 may be advanced throughthe clot material CM such that a distal terminus of the guidewire 1 isdistal of the clot material CM. Next, a delivery catheter 2 may bedelivered over the guidewire 1 so that a distal portion of the deliverycatheter 2 is positioned at or near the clot material CM. As shown inFIG. 2B, in some embodiments the delivery catheter 2 may be advancedover the guidewire 1 through the clot material CM such that a distalterminus of the delivery catheter 2 is distal of the clot material CM.With the delivery catheter 2 in position, the guidewire 1 may bewithdrawn. The clot retrieving device 10 may then be advanced throughthe delivery catheter 2 in a low-profile configuration until a distalterminus 101 of the capture structure 100 (shown schematically in FIG.2B) is at or adjacent the distal terminus of the delivery catheter 2. Asshown in FIGS. 2C and 2D, the delivery catheter 2 may then be pulledproximally relative to the clot retrieving device 10 to release thecapture structure 100, thereby allowing the capture structure 100 toself-expand within the clot material CM. As the capture structure 100expands, the capture structure 100 engages and/or secures thesurrounding clot material CM, and in some embodiments may restore orimprove blood flow through the clot material CM. In some embodiments,the capture structure 100 may be expanded distal of the clot material CMsuch that no portion of the capture structure 100 is engaging the clotmaterial CM while the capture structure 100 is in the process ofexpanding toward the vessel wall. In some embodiments, the capturestructure 100 is configured to expand into contact with the blood vesselwall, or the capture structure 100 may expand to a diameter that is lessthan that of the blood vessel lumen such that the capture structure 100does not engage the entire circumference of the blood vessel wall.

As shown in FIG. 2D, the delivery catheter 2 may continue advancingproximally to release the cover 200 such that at least a portion of thecover wall 200 c expands into contact with the blood vessel wall and thecover 200 is in the first position. Once the delivery catheter 2 ismoved proximal of the cover 200 in the first position and both the cover200 and the capture structure 100 are expanded within the vessel lumen,the retrieval assembly 14 is in the first configuration.

As shown in FIG. 2E, when the elongated shaft 12 is pulled proximallywhile the retrieval assembly 14 is in the first configuration, frictionbetween the blood vessel wall and the cover wall 200 c prevents orresists proximal movement of the free second end portion 200 b of thecover 200 while the first end portion 200 a of the cover 200 moves in aproximal direction with the capture structure 100. In other words,expansion of the cover 200 provides sufficient friction against thewalls of the vessel V to overcome the column strength of the cover wall200 c, thereby causing the cover wall 200 c to remain in place and/ormove less than the first end portion 200 a of the cover 200 so that thecover wall 200 c inverts over the proximally advancing capture structure100 and any associated clot material CM. As the elongated shaft 12 ismoved proximally and the cover 200 is inverting, the capture structure100 moves proximally relative to the leading edge 204 of the cover 200so that the length of the capture structure 100 coextensive with thecover 200 increases. Eventually, the cover 200 completely inverts fromthe first position over the capture structure 100, thereby furthersecuring any clot material held by or within the capture structure. Asshown in FIG. 2G, the clot retrieving device 10 may continue advancingproximally until the retrieval assembly 14 is positioned within thedelivery catheter 2. The delivery catheter 2, device 10, and associatedclot material CM may then be withdrawn from the patient.

2.0 SELECTED EMBODIMENTS OF COVERS AND ASSOCIATED METHODS OF USE

FIGS. 3A-8C show various embodiments of covers for use with the clotretrieving devices of the present technology. Although the coversdiscussed below are described with reference to the clot retrievingdevice 10 shown in FIGS. 1A-2G, any of the covers disclosed herein maybe used with any of the clot retrieval devices disclosed herein. Forexample, any of the covers discussed below may be used with any of theconnection assemblies discussed with reference to FIGS. 9A-15.

FIGS. 3A and 3B are side views of a retrieval assembly 344 of a clotretrieving device 340 shown outside of a blood vessel in an expanded,relaxed (e.g., unconstrained) configuration in accordance with thepresent technology. The clot retrieving device 340 and retrievalassembly 344 can include components that are generally similar instructure and function as those of the clot retrieving device 10 shownin FIGS. 1A-2G. For example, the clot retrieving device 340 includes theelongated shaft 12 and the connection assembly 300. As such, common actsand structure are identified by the same reference numbers, and onlysignificant differences in operation and structure are described below.

The retrieval assembly 344 may include the capture structure 100 and acover 350 coupled to the elongated shaft 12 by the connection assembly300. In some embodiments, the capture structure 100 and the cover 350are fixed to the elongated shaft 12 at generally the same location, orthe capture structure 100 and cover 200 may be coupled to the shaft 12at different locations and/or may be slidable with respect to theelongated shaft 12. Additional details regarding the connection assembly300 and relative positions of the capture structure 100 and cover 350are described in greater detail below with reference to FIGS. 9A-15.

The cover 350 may be a mesh structure. For example, in some embodimentsthe cover 350 is a braided tube having one or more preset shapes. Thecover 350 can comprise a mesh and/or braid of a plurality of wires(e.g., filaments, threads, sutures, fibers or the like) that have beeninterwoven to form a structure having openings (e.g., a porous fabric).The mesh and/or braid can be composed of metals, polymers, composites,and/or biologic materials. Polymer materials can include Dacron,polyester, polypropylene, nylon, Teflon, polytetrafluoroethylene (PTFE),tetrafluoroethylene, polyethylene terephthalate, polyactic acid (PLA)silicone, polyurethane, polyethylene, polycarbonate, styrene, polyimide,PEBAX, Hytrel, polyvinyl chloride, high-density polyethylene,low-density polyethylene, polyether ether ketone (PEEK), rubber, latex,and/or other suitable polymers known in the art. Other materials knownin the art of elastic implants can also be used. Metal materials caninclude, but are not limited to, nickel-titanium alloys (e.g. Nitinol),platinum, cobalt-chromium alloys, stainless steel, tungsten or titanium.In certain embodiments, metal filaments may be highly polished orsurface treated to further improve their hemocompatibility. The cover350 can be constructed solely from metallic materials without theinclusion of any polymer materials, solely from polymer materialswithout the inclusion of any metallic materials, or a combination ofpolymer and metallic materials.

In some embodiments, some or all of the wires of the cover 350 are DFTwires having a radiopaque core (e.g., platinum, tantalum, gold,tungsten, etc.) surrounded by a superelastic material (e.g., Nitinol, acobalt-chromium alloy, etc.). The radiopaque core may comprise about 5%to about 50% (e.g., 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%) of thetotal-cross-sectional area of the individual wires. In some embodiments,the cover 200 may have 72-144 total wires (e.g., 72, 96 128, 144, etc.)Moreover, some or all of the wires may have a wire diameter of about0.005 inches to about 0.015 inches (e.g., 0.008 inches, 0.01 inches,etc.). In some embodiments, all of the wires have the same diameter, andin other embodiments some of the wires have different diameters.

The cover 350 includes a first end portion 350 a coupled to the shaft 12via the connection assembly 300, a free second end portion 350 b, and acover wall 350 c extending between the first end portion 350 a and thesecond end portion 350 b. As used herein to describe the second endportion 350 b of the cover 350, the term “free” refers to a portion ofthe cover 350 that is not fixed to the elongated shaft 12 and may moveradially and/or longitudinally with respect to the shaft 12. As shown inFIGS. 3A and 3B, the cover wall 350 c includes a body portion 358 and anend portion 356 extending from the body portion 358. The cover 350 isflexible such that it is movable between a first position (FIG. 3A) inwhich the free second end portion 350 b is proximal of the first endportion 350 a and a second position (FIG. 3B) in which the cover 350 isinverted over the capture structure 100 such that a distal terminus 345(FIG. 3B) of the cover 350 is at or distal to the distal terminus 101 ofthe capture structure 100.

As shown in FIG. 3A, when the cover 350 is in the first position in anexpanded, relaxed state, the cover 350 may have a leading edge 354 thatoverlaps the coupling region 102 of the capture structure 100 but doesnot extend beyond the coupling region 102 to overlap the body 108 of thecapture structure 100. The leading edge 354 of the cover 350 mayalternatively overlap all or a portion of the length of the body 108when the cover 350 is in the first position. As shown in FIG. 3B, whenthe cover 350 is in the second position, the free second end portion 350b is distal of the first end portion 350 a and distal of the distalterminus 101 of the capture structure 100. As such, when in the secondposition, the body portion 358 of the cover wall 350 c defines anaxially extending cavity 360 and the capture structure 100 is positionedwithin the cavity 360.

When the cover 350 is in the first configuration (FIG. 3A), the endportion 356 extends proximally from the body portion 358, and each ofthe body portion 358 and/or the end portion 356 may have a generallytubular shape. In the illustrated embodiment, the end portion 356 has across-sectional dimension (e.g., cross-sectional area, diameter, etc.)that is greater than a cross-sectional dimension (e.g., cross-sectionalarea, diameter, etc.) of the body portion 358. In other embodiments, thebody portion 358 and/or the end portion 356 may have different shapesand/or relative sizes. As shown in FIG. 3B, when the cover 350 is in thesecond configuration, the body portion 358 may have a generally tubularshape, and at least a region of the end portion 356 may taper inwardlyin a distal direction. The end portion 356 may define a channel 362extending therethrough that is continuous with the cavity 360 andterminates at an opening 364.

FIGS. 3C and 3D are enlarged side and isometric views, respectively, ofthe end portion 356 of the cover 350 in the second configuration. Thecover 350 is shown without a braided pattern in FIGS. 3C and 3D for easeof viewing and describing the various regions of the end portion 356. Asshown in FIGS. 3C and 3D, the end portion 356 may be heat set to have apredetermined shape in the expanded, relaxed state such that at least alength of the end portion 356 distal to a distal terminus 101 of thecapture structure 100 (FIG. 1B) tapers radially inwardly, therebyenclosing associated clot material and preventing or otherwise reducingthe escape of particles from an interior region of the cover 350. Forexample, the end portion 356 may have a preset shape in the secondconfiguration such that the cover wall 350 c folds onto itself one ormore times, thereby forming a first region 356 a extending distally andradially inwardly from the body portion 358 (visible in FIG. 3C only), asecond region 356 b extending distally and radially outwardly from thefirst region 356 a, a broad or third region 356 c extending proximallyfrom the second region 356 b, and an optional inverted or fourth region356 d extending distally from the third region 356 c to a free edge 369.The first region 356 a and the second region 356 b may together form aneck 370 (FIG. 3C) that defines the channel 362 extending through theend portion 356. As such, the channel 362 has a cross-sectionaldimension that may decrease then increase in a distal direction. In someembodiments, the fourth region 356 d defines the most radially outwardportion of the end portion 356.

In some embodiments, the second region 356 b and the third region 356 cmay together define a curved distal face 366 of the end portion 356and/or cover 350, and the third region 356 c and the fourth region 356 dmay meet at a proximal, creased and/or folded edge 368 of the endportion 356. The distal terminus 345 of the cover 350 may coincide withthe portion of the distal face 366 where the second region 356 b meetsthe third region 356 c. In some embodiments, the free edge 369 of thefourth region 356 d is proximal of the distal face 366. Overlappingportions of the neck 370 and third region 356 c may be in contact withone another or may be separated by a distance d₁ (FIG. 3C), andoverlapping portions of the third region 356 c and the fourth region 356d may be in contact with one another or may be separated by a distanced₂ (FIG. 3C). In some embodiments distance d₁ is greater than distanced₂.

The end portion 356 of FIGS. 3B-3D advantageously facilitates manuallyretracting the cover 350 following an initial use of the cover andcapture structure 100. After an initial use of the retrieval device 340,at which point it will have reached the configuration shown in FIG. 3B,it may be necessary to perform a “second pass” with the device so as toretrieve any clot that remain in the treatment area following the firstpass. The clinician can grasp the end portion 356 gently between thethumb and forefinger and urge it in the proximal direction to begin theprocess of retraction. The cover 356 can be retracted in this manneruntil it reaches the initial, or fully retracted, configuration shown inFIG. 3A. At this point the capture structure 100 can be cleaned of anyretrieved thrombus and the device 340 can be used for a second pass, andany subsequent passes, until a satisfactory removal of thrombus has beenachieved.

The broadened and “curled-back” shape of the end portion 356 facilitatesmanual retraction of the cover and subsequent re-use of the device 340,which can be difficult with a device, such as the clot retrieving device10, that lacks such a feature. For example, as shown in FIG. 1B, whenthe cover forms a collapsed, inwardly tapered distal end in the evertedor deployed configuration, it can be difficult to push it proximally or“peel back” the cover wall so as to reverse the process of everting. Thebroadened shape of the end portion 356 allows it to be easily graspedand pushed proximally, while the curled-back shape of the cover wall inthe end portion 356 helps to cause the cover to reverse or undo itseverted configuration during retraction. Note that these functions andproperties apply to the end portion 356 shown in FIGS. 3A-3D, as well asthe end portions 356 shown in FIGS. 4A-4N.

In several embodiments, the end portion 356 may have other shapes and/orconfigurations when the cover 350 is in the second configuration in anexpanded, relaxed state. For example, although the cover wall 350 calong the end portion 356 is folded on itself two times in the exampleshown in FIGS. 3A-3D, the end portion 356 may be folded on itself moreor fewer than two times. For example, in some embodiments the endportion 356 may not be folded on itself, or the end portion 356 may befolded on itself only one time such that the end portion 356 onlyincludes the first through third regions 356 a-356 c and does notinclude the fourth region 356 d as shown in FIG. 4A. In someembodiments, the end portion 356 may be folded on itself three timessuch that it includes a fifth region 356 e extending proximally from thefourth region 356 d (FIG. 4F).

As shown in FIG. 4B, in some embodiments the free edge 369 of the fourthregion 356 d may be distal of the distal face 366, and the fourth region356 d may extend generally parallel to a longitudinal axis L of the endportion 356. In some embodiments, the fourth region 356 d may extenddistally and radially outwardly and be concave towards the third region356 c (FIG. 4C), and in some embodiments the fourth region 356 d mayextend distally and radially outwardly and be convex towards the thirdregion 356 c (FIG. 4D). In some embodiments, the fourth region 356 d mayextend distally and radially outwardly, then radially inwardly (FIG.4E). As shown in FIG. 4G, in some embodiments the portion of the cover350 comprising the folded edge 368 may extend radially outwardlygenerally perpendicular to the longitudinal axis L of the end portion356 for a distance d. In some embodiments the folded edge 368 may beproximal of the first region 356 a (FIG. 4H), or the folded edge 368 maybe distal of the first region 356 a (FIGS. 4I and 4M). In someembodiments, the neck 370 may include an intermediate region 356 fbetween the first and second regions 356 a, 356 b that has a generallyconstant diameter (FIG. 4J).

As shown in FIG. 4K, in some embodiments the second region 356 b extendsdistally from the first region 356 a generally parallel to thelongitudinal axis L of the end portion 356, then extends radiallyoutwardly generally perpendicular to the longitudinal axis L so that thedistal face 366 of the end portion 356 and/or cover 350 is generallyflat (in contrast to the curved distal face 366 in FIG. 3C). As such, across-sectional dimension of the neck 370 tapers in a distal directionthen remains generally constant such that the neck 370 does not includea portion that extends radially outwardly. Moreover, as shown in FIG.4L, in some embodiments the neck 370 tapers down distally to a pinchedportion 357 at or along which all or a portion of the cover wall comestogether such that the channel 362 is at least partially blocked. Insome embodiments, the body portion 358 may have a diameter D₁ that isgreater than the diameter D₂ of the end portion 356 when the cover 350is in a relaxed, expanded state (FIG. 4M).

In some embodiments, the diameter D₁ of the body portion 358 is lessthan or equal to the diameter D₂ of the end portion 356 when the cover350 is in a relaxed, expanded state (FIG. 3B). As shown in FIG. 4N, insome embodiments, the end portion 356 includes a transition region 356 ibetween the second region 356 b and the third region 356 c. Thetransition region 356 i may extend radially outwardly from the secondregion 356 b generally perpendicular to the longitudinal axis L of theend portion 356 (i.e., the transition region 356 i generally does notextend distally or proximally). In such embodiments, at least a portionof the distal face 366 of the end portion 356 and/or cover 350 isgenerally flat. In addition, also as shown in FIG. 4N, in someembodiments at least a portion of the third region 356 c may extendproximally and generally parallel to the longitudinal axis L of the endportion 356 (i.e., not radially outwardly as shown in FIG. 3C).

In use, the clot retrieving device 340 may be delivered through adelivery catheter 2 (e.g., a microcatheter) to a treatment site within ablood vessel lumen (e.g., a cerebral blood vessel) as described abovewith reference to FIGS. 2A and 2B. The delivery catheter 2 may then bepulled proximally relative to the clot retrieving device 340 to releasethe capture structure 100, thereby allowing the capture structure 100 toself-expand within the clot material CM as described above withreference to FIG. 2C. The delivery catheter 2 may continue advancingproximally to release the cover 350 such that at least a portion of thecover wall 350 c expands into contact with the blood vessel wall and thecover 350 is in the first position. FIG. 5A, for example, shows theretrieval assembly 344 expanded within the blood vessel lumen in a firstconfiguration. As discussed above, in some embodiments, when the cover350 is in the first position in a relaxed, expanded state, the endportion 356 may have a cross-sectional dimension (e.g., cross-sectionalarea, diameter, etc.) that is greater than a cross-sectional dimension(e.g., cross-sectional area, diameter, etc.) of the body portion 358.Accordingly, when the cover 350 is expanded within the blood vessel,both the body portion 358 and the end portion 356 may expand intocontact with the blood vessel wall, but the end portion 356 exerts agreater radially outward force on the vessel wall V than the bodyportion 358. As such, when the retrieval assembly 344 is pulledproximally, the end portion 356 of the cover 350 resists proximalmovement to a greater extent than the body portion 358. In someembodiments, only the end portion 356 expands into contact with theblood vessel wall V.

FIG. 5B is a side view of the retrieval assembly 344 in the blood vesselin a second configuration and with the cover 350 in a second, invertedposition. As shown in FIG. 5B, when the cover 350 is in the secondposition in the blood vessel lumen, both the body portion 358 and thebroad portion of the end portion 356 (e.g., the third and/or fourthregions 356 c, 356 d (FIG. 3C)) are in apposition with the blood vesselwall V, while the neck 370 (see FIG. 3C) is not in contact with theblood vessel wall V. As such, as the retrieval assembly 344 is pulledproximally, captured clot material CM having a size greater than thediameter of the channel 362 is prevented from escaping the cavity 360.

FIG. 6A is a cross-sectional side view of one embodiment of a retrievalassembly 602 of a clot retrieving device 600 shown outside of a bloodvessel in an expanded, relaxed configuration in accordance with thepresent technology. The clot retrieving device 600 and retrievalassembly 602 can include components that are generally similar instructure and function as those of the clot retrieving device 10 shownin FIGS. 1A-2G. For example, the clot retrieving device 600 includes theelongated shaft 12, and the retrieval assembly 602 includes the capturestructure 100 (only a portion shown for ease of illustration). As such,common acts and structure are identified by the same reference numbers,and only significant differences in operation and structure aredescribed below.

The retrieval assembly 602 may include the capture structure 100 and acover 604. The proximal region 100 a of the capture structure 100 may becoupled to the shaft 12 by connector 607, and a proximal region 604 a ofthe cover 604 may be coupled to the shaft 12 by connector 605. Connector605 may be positioned along the shaft 12 proximal of connector 607. Theconnector 607 can be similar to the connector 1201 (and any variationsthereof) described with respect to FIGS. 12A-15, and the connector 605can be similar to the connectors 901, 1001, 1101 (and any variationsthereof) described with respect to FIGS. 9A-15.

In some embodiments, the connector 607 and/or proximal region 100 a ofthe capture structure 100 is fixed to the shaft 12, and the connector605 and/or proximal region 604 a of the cover 604 is slidably coupled tothe shaft 12. As such, the connector 607 and/or proximal region 100 a ofthe capture structure 100 is movable along the shaft 12 relative to theconnector 605 and/or proximal region 604 a of the cover 604. In thoseembodiments where the cover 604 is slidably attached to the shaft 12,the clot retrieving device 600 may include a stop 609 fixed to the shaft12 proximal of connector 605 that prevents axial movement of connector605 along the shaft 12 proximal of the stop 609. For example, the stop609 and/or connector 607 may have a shape and size that inhibit movementof the cover 604 and/or connector 605. In some embodiments, the stop 609and/or connector 607 can have an outer dimension that is larger than aninterior dimension of connector 605 (or vice versa) such that movementof the connector 605 distally beyond connector 607 and/or proximallybeyond stop 609 is inhibited or prevented. In some embodiments, the stop609 may be formed integrally with the shaft 12. In several embodiments,the clot retrieving device 600 may include more than one stop. In someembodiments, the stop 609 can comprise a radiopaque material.

In some embodiments, the cover 604 and/or connector 605 can be fixedlyattached to the shaft 12. The cover 604 and/or connector 605 can befixedly attached to the shaft 12 by, for example, soldering, welding,crimping, adhesive(s), or a combination thereof. In some embodiments,the cover 604 and/or connector 605 can be rotatably coupled to the shaft12. For example, in some embodiments, the cover 604 and/or connector 605may be slidably and rotatably coupled to the shaft 12. In someembodiments, the connector 605 may be fixed at a certain axial locationalong the shaft 12 but is still free to rotate about the shaft 12. Inany of the foregoing embodiments, the capture structure 100 and/orconnector 607 can be slidably and/or rotatably coupled to the shaft 12.

As shown in FIG. 6A, the cover 604 may be formed of a two-layer meshstructure having an inner layer 606 and an outer layer 608. The innerlayer 606 may be continuous with the outer layer 608 at a distalterminus 611 of the cover 604, and the proximal end portions of theinner and outer layer 606, 608 may be fixed relative to one another atconnector 605. As such, the cover 604 may have a closed proximal region604 a. The cover 604 may include an opening 612 at its distal region 604b, and the inner layer 606 may define a cavity 610 that extends distallyfrom connector 605 along the length of the cover 604 and terminates atthe opening 612. The cavity 610 and/or opening 612 may be configured toreceive the elongated shaft 12 and the capture structure 100 therein. Insome embodiments, the cover 604 may be formed of an inverted tubularbraid such that the distal terminus 611 of the cover 604 may comprise afolded edge of the braid and the first and second ends of the tubularbraid are adjacent one another at a proximal region 604 a of the cover604. The folded edge may surround and define the opening 612 at thedistal region 604 b of the cover 604.

In those embodiments where the cover 604 is a mesh and/or braid, thecover 604 may include a plurality of wires (e.g., filaments, threads,sutures, fibers or the like) that have been interwoven to form astructure having openings (e.g., a porous fabric). The mesh and/or braidcan be composed of metals, polymers, composites, and/or biologicmaterials. Polymer materials can include Dacron, polyester,polypropylene, nylon, Teflon, polytetrafluoroethylene (PTFE),tetrafluoroethylene, polyethylene terephthalate, polyactic acid (PLA)silicone, polyurethane, polyethylene, polycarbonate, styrene, polyimide,PEBAX, Hytrel, polyvinyl chloride, high-density polyethylene,low-density polyethylene, polyether ether ketone (PEEK), rubber, latex,and/or other suitable polymers known in the art. Other materials knownin the art of elastic implants can also be used. Metal materials caninclude, but are not limited to, nickel-titanium alloys (e.g. Nitinol),platinum, cobalt-chromium alloys, stainless steel, tungsten or titanium.In certain embodiments, metal filaments may be highly polished orsurface treated to further improve their hemocompatibility. The cover604 can be constructed solely from metallic materials without theinclusion of any polymer materials, solely from polymer materialswithout the inclusion of any metallic materials, or a combination ofpolymer and metallic materials.

In some embodiments, some or all of the wires of the cover 604 are DFTwires having a radiopaque core (e.g., platinum, tantalum, gold,tungsten, etc.) surrounded by a superelastic material (e.g., Nitinol, acobalt-chromium alloy, etc.). The radiopaque core may comprise about 5%to about 50% (e.g., 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%) of thetotal-cross-sectional area of the individual wires. In some embodiments,the cover 200 may have 72-144 total wires (e.g., 72, 96 128, 144, etc.)Moreover, some or all of the wires may have a wire diameter of about0.005 inches to about 0.015 inches (e.g., 0.008 inches, 0.01 inches,etc.). In some embodiments, all of the wires have the same diameter, andin other embodiments some of the wires have different diameters.

As shown in FIG. 6A, in some embodiments the cover 604 may have aproximal portion 620, an intermediate portion 632, and a distal portion634. The proximal portion 620 may extend from the connector 605 to aproximal terminus of the intermediate portion 632, the intermediateportion 632 may extend from a distal terminus of the proximal portion620 to a proximal terminus of the distal portion 634, and the distalportion 634 may extend from a distal terminus of the intermediateportion 632 to a distal terminus 611 of the cover 604. At least when thecover 604 is in an expanded, relaxed state (as shown in FIG. 6A), theinner layer 606 may have (a) a first cross-sectional dimension IL₁ atthe proximal portion 620 of the cover 604, (b) an increasing secondcross-sectional dimension IL₂ along the intermediate portion 632 of thecover 604, and (c) a third cross-sectional dimension IL₃ at the distalportion 634 of the cover 604 that is greater than the firstcross-sectional dimension IL₁. In some embodiments, the firstcross-sectional dimension IL₁ of the inner layer 606 is generallyconstant along the proximal portion 620 of the cover 604, and the thirdcross-sectional dimension IL₃ of the inner layer 606 is generallyconstant along the distal portion 634 of the cover 604.

FIG. 6B is an enlarged view of a portion of the cover 604 shown in FIG.6A. As shown in FIG. 6B, in some embodiments the inner layer 606 isconvex towards the cavity 610 along the intermediate portion 632. Insome embodiments, the inner layer 606 is concave towards the cavity 610along the intermediate portion 632. In some embodiments, the inner layer606 has a proximal region 631 and a distal region 633 along theintermediate portion 632. As shown in FIG. 6B, in some embodiments, theproximal region 631 is convex towards the cavity 610, and the distalregion 633 is concave towards the cavity 610. In some embodiments, theproximal region 631 is concave towards the cavity 610, and the distalregion 633 is convex towards the cavity 610.

Referring again to FIG. 6A, at least when the cover 604 is in theexpanded, relaxed state, the outer layer 608 of the cover 604 may have afirst cross-sectional dimension OL₁ that is generally constant along thedistal portion 634 and the intermediate portion 632 of the cover 604.The first cross-sectional dimension OL₁ of the outer layer 608 may begreater than an inner diameter of the portion of the blood vesseladjacent to the clot material such that, when the cover 604 is expandedwithin a portion of the blood vessel V (see FIG. 7), the outer layer 608exerts a radially outward force on the blood vessel wall along at leastthe distal and intermediate portions 634, 632 of the cover 604. In someembodiments, at least when the cover 604 is in an expanded, relaxedstate, the outer layer 608 along the proximal portion 620 of the cover604 has a proximal region 622 and a distal region 624. As shown in FIG.6A, the proximal region 622 may extend distally from the connector 605to a proximal terminus of the distal region 624, and the distal region624 may extend distally from a distal terminus of the proximal region622 to a proximal terminus of the intermediate portion 620. In someembodiments, a cross-sectional dimension of the proximal region 622decreases in a proximal direction, and the distal region 624 has agenerally constant cross-sectional dimension. Moreover, thecross-sectional dimension of the distal region 624 may be substantiallythe same as the cross-sectional dimension along the distal andintermediate portions 632, 634 of the cover 604.

FIG. 7 is a side view of the retrieval assembly 602 positioned in ablood vessel V (e.g., a cerebral blood vessel) at a treatment site in anexpanded state. In use, the retrieval assembly 602 may be deliveredthrough a delivery catheter 2 (e.g., a microcatheter) to the treatmentsite as described above with reference to FIGS. 2A and 2B. The deliverycatheter 2 may then be pulled proximally relative to the retrievalassembly 602 to release the capture structure 100, thereby allowing thecapture structure 100 to self-expand within the clot material CM asdescribed above with reference to FIG. 2C. The delivery catheter 2 maycontinue advancing proximally to release the cover 604 such that atleast a portion of the outer layer 608 expands into contact with thewall of the blood vessel V.

With the capture structure 100 engaging the clot material CM, theelongated shaft 12 may be pulled proximally. Friction between the outerlayer 608 and the vessel wall V holds the cover 604 in place within theblood vessel lumen and/or resists proximal movement to a greater degreethan the capture structure 100. As such, the elongated shaft 12 slidesproximally through the cavity 610 and connector 605 and pulls thecapture structure 100 proximally through the opening 612 at the distalregion 604 b of the cover 604, as shown in FIG. 8A. As shown in FIG. 8B,as the capture structure 100 is pulled through the narrow cavity 610,the capture structure 100 forces the inner layer 806 radially outwardlyalong the portion of the inner layer 806 aligned with the capturestructure 100. Once the capture structure 100 is completely within thecavity 610, the inner layer 606 collapses radially inwardly distal of adistal terminus 101 of the capture structure 100, thereby forming anarrowed or substantially or completely closed region 630 and enclosingthe capture structure 100 within the inner layer 606. Such narrowing orclosure of the region 630 helps prevent the escape of thrombus from thecapture structure 100 and/or cover 604 during withdrawal of the device600 from the blood vessel V.

Once the connector 605 abuts connector 607 and/or stop 609, proximalmovement of the elongated shaft 12 pulls the cover 604 and the capturestructure 100 proximally together. As shown in FIG. 8C, the clotretrieving device 600 may continue advancing proximally until theretrieval assembly 602 is positioned within the delivery catheter 2. Thedelivery catheter 2, device 600, and associated clot material CM maythen be withdrawn from the patient.

The cover 604 of FIGS. 6A-8C can be easily retracted to the initialposition shown in FIG. 6A to facilitate performing a second (andsubsequent) “pass” to retrieve any thrombus that may remain in thetreatment area following a first pass. After the first pass (see FIG.8C), the cover 604 can be easily grasped, e.g. at the connector 605, andretracted proximally to the position shown in FIG. 6A by sliding italong the shaft 12. Because the cover 604 does not evert during theprocess of covering the capture structure 100, there is no need toreverse any eversion during retraction. This in turn allows for asimpler retraction process. Following retraction of the cover 604, thecapture structure 100 can be cleaned of any thrombus and used in thesecond and subsequent passes.

3.0 SELECTED EMBODIMENTS OF CONNECTION ASSEMBLIES AND ASSOCIATED METHODSOF USE

FIGS. 9A-15 show various embodiments of connection assemblies for usewith the clot retrieving devices of the present technology. Although theconnection assemblies discussed below are described with reference tothe clot retrieving device 10 shown in FIGS. 1A-2G, any of theconnection assemblies may be used with any of the clot retrievingdevices, capture structures, and/or covers disclosed herein. Forexample, any of the connection assemblies discussed below may be usedwith any of the covers discussed above with reference to FIGS. 3A-8C.Moreover, only the first end portion 200 a of the cover 200 and proximalportion 100 a of the capture structure 100 are shown in FIGS. 9A-15 forease of illustration.

FIGS. 9A and 9B are side and isometric enlarged views, respectively, ofone embodiment of a connection assembly 900 of a clot retrieving device940 shown outside of a blood vessel in accordance with the presenttechnology. The clot retrieving device 940 can include components thatare generally similar in structure and function as those of the clotretrieving device 10 shown in FIGS. 1A-2G. For example, the clotretrieving device 940 includes the elongated shaft 12, the capturestructure 100, and the cover 200. As such, common acts and structure areidentified by the same reference numbers, and only significantdifferences in operation and structure are described below.

As shown in FIGS. 9A and 9B, in some embodiments of the clot retrievingdevice 940, the coupling region 102 of the capture structure 100 mayinclude an opening 104, and a coupling region 16 of the shaft 12 mayextend through the opening 104. For example, the coupling region 16 ofthe shaft 12 can include a first region 18, a second region 20 (onlyvisible in FIG. 9B), and a bend 22 between the first and second regions18 and 20. In some embodiments, the coupling region 16 can form a hooksuch that the elongated shaft 12 is bent back on itself (e.g.,approximately 180 degrees) and the second region 20 of the shaft 12 isproximal of the bend 22 and the opening 104. In other embodiments, thecapture structure 100 may be coupled to the shaft 12 via otherconnection means.

The connection assembly 900 may include a connector 901 that comprisesan outer band 902 and an inner band 904. The inner band 904 ispositioned around a portion of the elongated shaft 12, and the outerband 902 is located radially outwardly of the inner band 904. At least aportion of the outer band 902 may be axially aligned and/or overlap withat least a portion the length of the inner band 904. In some embodimentsof the device in FIGS. 9A and 9B, the inner band 904 is positionedaround the interconnected coupling regions 16 and 102 of the shaft 12and the capture structure 100, respectively, and the first portion 200 aof the cover 200 is between the inner band 904 and the outer band 902.For example, the first portion 200 a of the cover can be clamped betweenthe outer band 902 and the inner band 904, or otherwise adhered to theouter and inner bands 902, 904. As such, the outer and inner bands 902,904 couple the cover 200 and the capture structure 100 to the shaft 12,and fix the first end portion 200 a of the cover 200 and the proximalportion 100 a of the capture structure 100 relative to one another andto relative to the elongated shaft 12. In some embodiments, theconnector 901 may include more or fewer than two bands.

Each of the inner band 904 and the outer band 902 can be generallycylindrical, or the inner band 904 and/or the outer band 902 may havedifferent shapes. The inner band 904 can have a cross-sectionaldimension that is about 0.027 inches or less, about 0.021 inches orless, and/or about 0.015 inches or less. The outer band 902 can have across-sectional dimension that is greater than that of the inner band904. The outer band 902 can have a cross-sectional dimension that isabout 0.027 inches or less, 0.021 inches or less, and/or 0.015 inches orless.

The inner band 904 includes a proximal terminus 950, a distal terminus944, and a length extending between the proximal terminus 950 and thedistal terminus 944. Likewise, the outer band 902 includes a proximalterminus 948, a distal terminus 946, and a length extending between theproximal terminus 948 and the distal terminus 946. In some embodiments,the proximal terminus 950 of the inner band 904 defines the proximalterminus of the connector 901 (alone or in conjunction with the outerband 902) and/or the distal terminus 944 of the inner band 904 definesthe distal terminus of the connector 901 (alone or in conjunction withthe outer band 902). Likewise, in some embodiments, the proximalterminus 948 of the outer band 902 defines the proximal terminus of theconnector 901 (alone or in conjunction with the inner band 904) and/orthe distal terminus 946 of the outer band 902 defines the distalterminus of the connector 901 (alone or in conjunction with the innerband 904).

As shown in FIGS. 9A and 9B, the inner band 904 and the outer band 902may have generally the same length, but the inner band 904 and the outerband 902 may have different lengths. In some embodiments, the proximalterminus 950 of the inner band 904 can be generally aligned with theproximal terminus 948 of the outer band 902 along a plane 952approximately normal to the elongated shaft 12 such that the proximalterminus 950 of the inner band 904 and the proximal terminus 948 of theouter band 902 are within about 0.005 inches of each other. Likewise,the distal terminus 944 of the inner band 904 can be generally alignedwith the distal terminus 946 of the outer band 902 along a plane 958approximately normal to the elongated shaft 12 such that the distalterminus 944 of the inner band 904 and the distal terminus 946 of theouter band 902 are within about 0.005 inches of each other.

In some embodiments the outer and inner bands 902, 904 are generallycoextensive along their entire respective lengths, but the outer andinner bands 902, 904 may be offset along the longitudinal axis of thedevice 10 and/or may have different lengths such that the outer andinner bands 902, 904 are generally coextensive along only a portion ofone or both of their respective lengths.

In some embodiments, the inner band 904 and/or outer band 902 caninclude a radiopaque material such as platinum, gold, tungsten,tantalum, platinum-iridium, and/or alloys of any of the foregoingmaterials. As such, the inner band 904 and/or outer band 902 may improvevisualization of the retrieval assembly 14. For example, visualizationof the connector 901 can assist the physician in confirming the locationof the retrieval assembly 14, or more specifically, the capturestructure 100, which may be distal to or generally aligned with theinner band 904 and/or outer band 902.

The connector 901 may be secured to the capture structure 100 andelongated shaft 12 by a crimp and/or a binding agent. For example, theinner band 904 may be secured to the capture structure 100 and/or theelongated shaft 12 by a crimp and/or a binding agent to fixedly attachthe inner band 904 to the elongated shaft 12. Moreover, the outer band902 may be secured to the first end portion 200 a of the cover 200 by acrimp and/or a binding agent to fixedly attach the outer band 902 andthe first end portion 200 a of the cover 200 to the inner band 904,elongated shaft 12, and/or capture structure 100. Suitable bindingagents include an adhesive, solder, welding flux, brazing filler, orother materials known and/or used in the art.

In some embodiments, the outer band 902, cover 200, and inner band 904are not fixed at a single location along the elongated shaft 12, butinstead are configured to rotate and/or translate along or relative tothe elongated shaft 12. In these embodiments, the clot retrieving device10 may include one or more stops (e.g., coils, bumpers, bands, secondconnectors, etc.) fixed at one or more locations along the elongatedshaft 12 proximal and/or distal to the connector 901, therebyrestricting axial movement of connector 901 (and associated first endportion 200 a of the cover 200 and proximal portion 100 a of the capturestructure 100) to a predetermined length of the elongated shaft 12. Anexample of one such embodiment is described in further detail below withrespect to FIGS. 12A-15.

The ability of the retrieval assembly 14 (e.g., the cover 200, capturestructure 100, and connector 901) to rotate may be advantageous torelieve at least some of the tortious stress built up during thedelivery of the clot retrieving device 10 through the vasculature. Aspreviously described, the device 10 is often advanced from a remote partof the body and into the cerebral region of the vasculature. Along thispath to a patient's treatment site, the device 10 may undergo manytwists and turns that result in tortious stress being exerted on thedevice 10. Such tortional stress can create difficulty when the device10 deploys from a retracted state to an expanded state. The ability torotate with respect to the elongated shaft 12 can help relieve thesestresses and improve control over deployment and positioning of theretrieval assembly 14.

The connector 901 can be assembled directly over the elongated shaft 12or over a sacrificial wire or tool. When the connector 901 is formedover the elongated shaft 12, the outer band 902, cover 200, and innerband 904 can be positioned sequentially over the elongated shaft 12(e.g., the outer band 902 first, then the cover 200, then the inner band904). This can wedge the first end portion 200 a of the cover 200between the outer band 902 and the inner band 904. The first end portion200 a of the cover 200 thus presses outwardly against both the innerband 904 and outer band 902, thereby creating a surface friction between(a) the cover 200 and (b) the outer surface of the inner band 904 andinner surface of the outer band 902 that is sufficient to secure thecover 200 between the inner and outer bands 904 and 902.

When the connector 901 is formed over a sacrificial wire or tool, theouter band 902, cover 200, and inner band 904 can be positionedsequentially (e.g., the outer band 902 first, then the cover 200, thenthe inner band 904) over a sacrificial wire having a larger outerdiameter than that of the elongated shaft 12 that the connector 980 isintended to be later inserted over. Once the outer band 902, cover 200,and inner band 904 are correctly positioned over the sacrificial wire,the outer band 902, cover 200, and inner band 904 can be, for example,crimped together and the sacrificial wire can be removed. The outer band902, cover 200, and inner band 904 can then be slideably positioned overthe elongated shaft 12. In such an embodiment, the outer band 902, cover200, and inner band 904 may not be secured to the elongated shaft 12 andcan be configured to move with respect to the elongated shaft 12, aspreviously described. Assembly of the connector 901 over a sacrificialwire, tool or mandrel in this manner allows for the connector 901 andcover 200 to be constructed separately from the shaft 12 and capturestructure 100, and subsequent joining of the connector 901 and cover 200to the shaft in a separate manufacturing step or location. This in turnoffers flexibility and efficiency in the manufacture of the retrievaldevice.

Once the connector 901 is assembled over the elongated shaft 12 orsacrificial wire or tool, the cover 200 may have wires 960 (e.g.,filaments) that protrude from the proximal terminus of the connector901. The protruding wires 960 can be trimmed to be generally alignedwith the plane 952 extending along the proximal terminus of theconnector 901. As such, the wires 960 can be trimmed to not protrude, orto protrude less, from the proximal terminus of the connector 901.

FIG. 10 is a cross-sectional side view of some embodiments of a clotretrieving device 1040 having a connection assembly 1000 configured inaccordance with the present technology. The connection assembly 1000 caninclude components that are generally similar in structure and functionas those of the connection assembly 900 in FIGS. 9A and 9B. For example,the connection assembly 1000 includes the connector 901, the outer band902, and the inner band 904 of the connection assembly 900, and allvariations of the foregoing as described above. As such, common acts andstructure are identified by the same reference numbers, and onlysignificant differences in operation and structure are described below.

The connection assembly 1000 shown in FIG. 10 includes first and secondjackets 1020 and 1042 at a proximal portion of the connector 901. Thefirst jacket 1020 (e.g., an inner sleeve) may be positioned over aproximal terminus 950 of the inner band 904 and a portion of theelongated shaft 12 proximal of the inner band 904. The second jacket1042 (e.g., an outer sleeve) may be positioned over a proximal terminus948 of the outer band 902 and the elongated shaft 12 proximal of theouter band 902. As such, the second jacket 1042 is positioned radiallyoutwardly of the first jacket 1020. In some embodiments, the connectionassembly 1000 may include only the first jacket 1020, or only the secondjacket 1042 (for example, as shown in FIG. 11).

As shown in FIG. 10, the proximal portion of the second jacket 1042directly contacts and is fixed to the elongated shaft 12, and theproximal portion of the first jacket 1020 directly contacts and is fixedto the elongated shaft 12 at a position distal of the fixed portion ofthe second jacket 1042. The second jacket 1042 may extend along all (see1046) or a portion of the outer surface of the outer band 902. Likewise,the first jacket 1020 may extend along all or a portion of the innerband 904. In some embodiments, the first and/or second jackets 1020 and1042 may be indirectly coupled to the shaft 12 via an intermediatestructure. For example, in some embodiments, the proximal portion of thefirst jacket 1020 is adhered to and in direct contact with the shaft 12and the proximal portion of the second jacket 1042 is adhered to and indirect contact with the proximal portion of the first jacket 1020. Insuch embodiments, the proximal portion of the first jacket 1020 ispositioned between the elongated shaft 12 and the proximal portion ofthe second jacket 1042 does not directly contact the elongated shaft 12.

The first and/or second jackets 1020 and 1042 can include a polymermaterial, including fluoropolymers such as polytetrafluoroethylene(PTFE). The first and/or second jackets 1020 and 1042 can also includepolyimide, polyether ether ketone (PEEK), polyurethane, nylon,polyethylene, polyamide, or combinations thereof. The first and/orsecond jackets 1020 and 1042 may also include elastic materials such asany heat-shrinkable material including but not limited to Pebax,polyurethane, silicone, and/or polyisoprene. When a heat-shrinkablematerial is used, the heat-shrinkable material can be applied over thedevice and heated such that the heat-shrinkable material is thermallybonded and compressed to adhere to the exterior of the inner and outerbands 904 and 902 and the elongated shaft 12. The jacket(s) can take theform of a mass of adhesive, solder or other solidified liquid (ratherthan a pre-existing sheet, tube or other body of solid material) that isapplied to the proximal terminus of the band(s) 902 and/or 904 so as tocover the wire ends.

As shown in FIG. 10, the first and/or second jackets 1020, 1042 may beadvantageous for providing a smooth or otherwise atraumatic surface atthe proximal edge of the connector 901. For example, in someembodiments, the cover 200 is composed of a plurality of wires and atleast some of the wires protrude proximally from the proximal terminus948 of the outer band 902. The second jacket 1042 covers the protrudingends of the wires to prevent the protruding ends from catching on thecover wall 200 c (FIGS. 1A and 1B) as the cover wall 200 c advances overthe connector 980 while it inverts over the capture structure 100 andalso to prevent trauma to the vessel walls.

FIG. 11 is a cross-sectional side view of clot retrieving device 1140having a connection assembly 1100 in accordance with the presenttechnology. The connection assembly 1100 can include components that aregenerally similar in structure and function as those of the connectionassemblies 900 and 1000. For example, the connection assembly 1100 caninclude the outer band 902 that is generally similar to that discussedabove with reference to FIGS. 9A and 9B. As such, common acts andstructure are identified by the same reference numbers, and onlysignificant differences in operation and structure are described below.

As shown in FIG. 11, the connection assembly 1100 includes a connector1101 comprising the outer band 902, an inner band 1104 having a proximalterminus 1150 extending proximally beyond the proximal terminus 948 ofthe outer band 902, and a jacket 1142 extending between the outer band902 and the inner band 1104. The inner band 1104 is generally similar tothe inner band 904 described above with respect to FIGS. 9A and 9B,except the inner band 1104 has a length that is greater than that of theouter band 902 and extends proximally beyond the distal terminus 946 ofthe outer band 902. In addition, the jacket 1142 can be generallysimilar to the second jacket 1042 described above with respect to FIG.10, except the jacket 1142 has a proximal portion adhered to an outersurface of the inner band 1104.

The connector 1101 shown in FIG. 11 may be configured to rotate aboutthe longitudinal axis of the shaft 12 and/or translate along the lengthof the elongated shaft 12. In other embodiments, the connector 1101 maybe secured to the elongated shaft 12 by a crimp and is not configured tomove with respect to the elongated shaft 12.

FIGS. 12A and 12B are cross-sectional side and isometric views of someembodiments of a clot retrieving device 1240 having a connectionassembly 1200 in accordance with the present technology. The connectionassembly 1200 can include components that are generally similar instructure and function as those of the connection assembly 900 in FIGS.9A and 9B. For example, the connection assembly 1200 can include theconnector 901 having the outer band 902 and the inner band 904 that aregenerally similar to those discussed above with reference to FIGS. 9Aand 9B. As such, common acts and structure are identified by the samereference numbers, and only significant differences in operation andstructure are described below. For example, in addition to the connector901 (referred to with respect to FIGS. 12A and 12B as “the firstconnector 901”), the connection assembly 1200 may include a secondconnector 1201 coupled to the elongated shaft 12 distal of and spacedapart from the first connector 901. In other embodiments, the firstconnector 901 may abut or otherwise be adjacent to and in contact withthe second connector 1201. Unlike connection assembly 900, the firstconnector 901 couples only the cover 200 (and not the capture structure100) to the elongated shaft 12, while the second connector 1201 couplesthe capture structure 100 to the shaft 12.

The second connector 1201 may comprise a single band 1204 similar to anyof the bands 902, 904, and 1104 described above with reference to FIGS.9A-11. For example, the band 1204 may have a generally cylindricalsidewall that defines a lumen 1208 therethrough. In some embodiments,the second connector 1201 and/or band 1204 may include a radiopaquematerial to improve visualization of the band 1204 and/or position ofthe proximal region 100 a of the capture structure 100. In otherembodiments, the band 1204 may have different shapes or components.Moreover, in some embodiments, the connector 1201 may include more thanone band. For example, in some embodiments the connector 1201 mayinclude an outer band surrounding at least a portion of the band 1204.

In the embodiment shown in FIGS. 12A and 12B, the shaft 12 extendsthrough a channel 908 defined by an interior surface of the inner band904 of the first connector 901, and the second connector 1201 and/orband 1204 is positioned around the interconnected coupling regions 16and 102 of the shaft 12 and the capture structure 100, respectively. Assuch, the second connector 1201 fixes the proximal portion 100 a of thecapture structure 100 to the elongated shaft 12. For example, the secondconnector 1201 and/or band 1204 can be secured to the capture structure100 and/or the elongated shaft 12 by a crimp and/or a binding agent. Thebinding agent may fill any void within the lumen 1208 of the band 1204and bond the second connector 1201 and/or band 1204 to the capturestructure 100 and/or the elongated shaft 12.

In some embodiments, the elongated shaft 12 is slidably received throughthe channel 908 such that the connector 901 (and associated cover 200)is movable axially along the shaft 12 and/or free to rotate about theshaft 12. At least in these embodiments, the second connector 1201 canhave an outer diameter D2 greater than an inner diameter D1 of the innerband 904. In such an embodiment, the second connector 1201 may serve asa mechanical stop and prevent the second connector 1201 from movingproximal of the first connector 901. In other embodiments, the firstconnector 901 is crimped or otherwise fixed to the shaft 12 such thatthe first connector 901 is not free to move axially and/or rotate.

FIG. 13 is a cross-sectional side view of some embodiments of a clotretrieving device 1340 having a connection assembly 1300 configured inaccordance with present technology. The connection assembly 1300 caninclude components that are generally similar in structure and functionas those of the connection assembly 1200 in FIGS. 12A and 12B. Forexample, the connection assembly 1300 includes the first connector 901and the second connector 1201 that are generally similar to thosediscussed above with reference to FIGS. 9A, 9B, 12A and 12B. As such,common acts and structure are identified by the same reference numbers,and only significant differences in operation and structure aredescribed below. For example, the connection assembly 1300 shown in FIG.13 includes a jacket 1342 (e.g., an outer sleeve) positioned extendingbetween the proximal terminus 948 of the outer band 902 and a portion ofthe elongated shaft 12 proximal of the outer band 902. In someembodiments, the connection assembly 1300 may include more than onejacket (e.g., two jackets, three jackets, etc.). For example, in someembodiments the connection assembly 1300 may include a jacket extendingproximally from the inner band 904 (such as jacket 1020 shown in FIG.10) to the shaft 12. The jacket 1342 may include any of the materialsdiscussed above with reference to jackets 1020 and 1042. As shown inFIG. 13, the proximal portion of the jacket 1342 directly contacts andis fixed to the elongated shaft 12, but alternatively the jacket 1342may be indirectly coupled to the shaft 12 via an intermediate structure(not shown) such that the proximal portion of the jacket 1342 does notdirectly contact the elongated shaft 12. The jacket 1342 may extendalong all (shown schematically in hashed lines) or a portion of theouter surface of the outer band 902.

Some embodiments of a connection assembly 1400 and clot retrievingdevice 1440 in accordance with the present technology are shown in thecross-sectional side view of FIG. 14. The connection assembly 1400 mayinclude the connection assembly 1100 of FIG. 11, as well as theconnector 1201 of FIGS. 12A and 12B. For example, the connectionassembly 1400 includes a connector 1401 comprising the outer band 902and the inner band 1104. The inner band 1104 may have a proximalterminus 1450 extending proximally beyond the proximal terminus 948 ofthe outer band 902. The connection assembly 1400 further includes ajacket 1142 extending between the outer band 902 and the inner band1104. In some embodiments, the connector 1401 shown in FIG. 14 may beconfigured to rotate about the longitudinal axis of the shaft 12 and/ortranslate along the length of the elongated shaft 12, or alternativelythe connector 1401 may be secured to the elongated shaft 12 by a crimpand is not configured to move with respect to the elongated shaft 12.

FIG. 15 is a cross-sectional side view of a connection assembly 1500configured in accordance with some embodiments of the presenttechnology. The connection assembly 1500 can include components that aregenerally similar in structure and function as those of the connectionassembly 1200 in FIGS. 12A and 12B. For example, the connection assembly1500 includes the first connector 901 and the second connector 1201discussed above with reference to FIGS. 12A and 12B. The connectionassembly 1500 may further include a stop 1550 (e.g., a bumper, band orcoil) fixed to the elongated shaft 12 and proximal of the connector 901.The stop 1550 can include an outer sleeve 1552 surrounding a coil 1554positioned around the elongated shaft 12. In some embodiments, such asthose embodiments wherein the connector 901 is configured to moveaxially along the elongated shaft 12, it may be desired for the outerdiameter D3 of the stop 1550 to be less than the outer diameter D1 ofthe inner band 904. In such an embodiment, the stop 1550 prevents theconnector 901 from moving proximally past the stop 1550. The stop 1550and/or the coil 1554 may also serve as a marker and include a radiopaquematerial. The coil 1554 may be formed of a metal and/or polymermaterial, and the sleeve 1552 may be a metal band crimped around thecoil 1554 and/or a polymer material that shrinks when heated. The stop1550 also provides mechanical support to the elongated shaft 12 over itslength. As such, a particular length, diameter, and pitch of the stop1550 can be selected to provide a desired flexibility/rigidity to theelongated shaft 12.

4.0 CONCLUSION

This disclosure is not intended to be exhaustive or to limit the presenttechnology to the precise forms disclosed herein. Although specificembodiments are disclosed herein for illustrative purposes, variousequivalent modifications are possible without deviating from the presenttechnology, as those of ordinary skill in the relevant art willrecognize. In some cases, well-known structures and functions have notbeen shown and/or described in detail to avoid unnecessarily obscuringthe description of the embodiments of the present technology. Althoughsteps of methods may be presented herein in a particular order, inalternative embodiments the steps may have another suitable order.Similarly, certain aspects of the present technology disclosed in thecontext of particular embodiments can be combined or eliminated in otherembodiments. Furthermore, while advantages associated with certainembodiments may have been disclosed in the context of those embodiments,other embodiments can also exhibit such advantages, and not allembodiments need necessarily exhibit such advantages or other advantagesdisclosed herein to fall within the scope of the present technology.Accordingly, this disclosure and associated technology can encompassother embodiments not expressly shown and/or described herein.

Throughout this disclosure, the singular terms “a,” “an,” and “the”include plural referents unless the context clearly indicates otherwise.Similarly, unless the word “or” is expressly limited to mean only asingle item exclusive from the other items in reference to a list of twoor more items, then the use of “or” in such a list is to be interpretedas including (a) any single item in the list, (b) all of the items inthe list, or (c) any combination of the items in the list. Additionally,the terms “comprising” and the like are used throughout this disclosureto mean including at least the recited feature(s) such that any greaternumber of the same feature(s) and/or one or more additional types offeatures are not precluded. Directional terms, such as “upper,” “lower,”“front,” “back,” “vertical,” and “horizontal,” may be used herein toexpress and clarify the relationship between various elements. It shouldbe understood that such terms do not denote absolute orientation.Reference herein to “one embodiment,” “an embodiment,” or similarformulations means that a particular feature, structure, operation, orcharacteristic described in connection with the embodiment can beincluded in at least one embodiment of the present technology. Thus, theappearances of such phrases or formulations herein are not necessarilyall referring to the same embodiment. Furthermore, various particularfeatures, structures, operations, or characteristics may be combined inany suitable manner in one or more embodiments.

I/We claim:
 1. A device for retrieving clot material from a bloodvessel, the device comprising: an elongated member having a distalregion configured to be intravascularly positioned at or near the clotmaterial within the blood vessel; and a cover having a proximal portion,an intermediate portion, and a distal portion, the cover slideablycoupled to the distal region of the elongated member at a connector, thecover having an inner layer and an outer layer continuous with the innerlayer at the distal terminus of the cover, wherein the proximal endportions of each of the inner layer and the outer layer are fixedrelative to one another at the connector, and wherein, at least when thecover is in an expanded, relaxed state: the inner layer has (a) a firstcross-sectional dimension at the proximal portion of the cover, (b) adistally increasing cross-sectional dimension along the intermediateportion of the cover, and (c) a second cross-sectional dimension at thedistal portion of the cover, wherein the second cross-sectionaldimension is greater than the first cross-sectional dimension, and theouter layer has a cross-sectional dimension that is generally constantalong the distal portion and the intermediate portion of the cover. 2.The device of claim 1 wherein the cross-sectional dimension of the outerlayer along the distal and intermediate portions of the cover is greaterthan an inner diameter of the portion of the blood vessel adjacent tothe clot material such that, when the cover is expanded within the bloodvessel lumen, the outer layer exerts a radially outward force on theblood vessel wall along at least the distal and intermediate portions ofthe cover.
 3. The device of claim 1 wherein, at least when the cover isin an expanded, relaxed state, the outer layer along the proximalportion of the cover has a distal region and a proximal region extendingproximally from the distal region to the connector, and wherein (a) thedistal region has a generally constant cross-sectional dimension, and(b) a cross-sectional dimension of the proximal region decreases in aproximal direction.
 4. The device of claim 3 wherein, at least when thecover is in an expanded, relaxed state, the cross-sectional dimension ofthe distal region of the outer layer is substantially the same as thecross-sectional dimension along the distal and intermediate portions ofthe cover.
 5. The device of claim 1 wherein, at least when the cover isin an expanded, relaxed state, the first cross-sectional dimension ofthe inner layer is generally constant along the proximal portion of thecover.
 6. The device of claim 1 wherein, at least when the cover is inan expanded, relaxed state, the second cross-sectional dimension of theinner layer is generally constant along the distal portion of the cover.7. The device of claim 1 wherein, at least when the cover is in anexpanded, relaxed state: the first cross-sectional dimension of theinner layer is generally constant along the proximal portion of thecover, and the second cross-sectional dimension of the inner layer isgenerally constant along the distal portion of the cover.
 8. The deviceof claim 1 wherein the distal terminus of the cover defines an openingconfigured to receive a capture structure therethrough, and wherein thecover includes a cavity extending proximally from the opening to theconnector.
 9. The device of claim 1 wherein the cover is an invertedtubular braid.
 10. The device of claim 1 wherein the elongated member isa solid wire.
 11. The device of claim 1, wherein, when the capturestructure is received in the cover, a first portion of the inner layeris displaced radially outward to accommodate the capture structure, anda second portion of the inner layer, located distal of the firstportion, remains collapsed radially inward to form at least a partialclosure distal of the capture structure.
 12. A system for retrievingclot material from a blood vessel, the system comprising: an elongatedmember having a distal region configured to be intravascularlypositioned at or near the clot material within the blood vessel; acapture structure having a proximal portion coupled to the distal regionof the elongated member at a first connector; and a cover coupled to thedistal region of the elongated member at a second connector, the secondconnector proximal of the first connector along the elongated member,wherein the cover has a first portion extending proximally from thedistal terminus, a second portion extending proximally from firstportion, and a third portion extending proximally from the secondportion to the second connector, wherein the cover has an inner layerand an outer layer continuous with the inner layer at the distalterminus of the cover, each of the inner layer and the outer layerhaving proximal ends fixed at the second connector, and wherein, atleast when the cover is in an expanded, relaxed state: the inner layerhas a funnel-shaped region along the first portion of the cover and aneck region extending along the second and third portions of the cover,and the outer layer has a generally cylindrical shape along the firstand second portions of the cover, and a decreasing cross-sectionaldimension along the third portion of the cover.
 13. The system of claim12 wherein the funnel-shaped region of the cover has a distal portionwith a generally constant cross-sectional dimension and a taperedproximal portion.
 14. The system of claim 12 wherein, at least when thecover is in an expanded, relaxed state, the distal terminus of the coversurrounds an opening configured to receive the capture structuretherethrough.
 15. The system of claim 14 wherein the inner layersurrounds a cavity extending from the opening to the third portion ofthe cover.
 16. The system of claim 12 wherein, as the capture structureis moved proximally along the neck region of the inner layer while thecover is expanded within the blood vessel such that the outer layercontacts with the blood vessel wall, a distance between the inner layerand the outer layer decreases along the portion of the cover axiallyaligned with the capture structure.
 17. The system of claim 12 whereinthe cover is an inverted tubular braid.
 18. The system of claim 12,wherein, when the capture structure is received in the cover, a firstportion of the inner layer is displaced radially outward to accommodatethe capture structure, and a second portion of the inner layer, locateddistal of the first portion, remains collapsed radially inward to format least a partial closure distal of the capture structure.
 19. A systemfor retrieving clot material from a blood vessel, the system comprising:an elongated member having a distal region configured to beintravascularly positioned at or near the clot material within the bloodvessel; a capture structure having a proximal portion coupled to thedistal region of the elongated member; and a dual-layer cover coupled tothe distal region of the elongated member at a location proximal of thecapture structure, wherein the cover has a radially expansile outerlayer that tends to self-expand toward an inner wall of the bloodvessel, and an inner layer that tends to collapse inward toward theelongated member such that the inner layer is spaced radially inwardfrom the outer layer; and the cover being slidable on the elongatedmember so that the capture structure can be received in the cover. 20.The system of claim 19, wherein, when the capture structure is receivedin the cover, a first portion of the inner layer is displaced radiallyoutward to accommodate the capture structure, and a second portion ofthe inner layer, located distal of the first portion, remains collapsedradially inward to form at least a partial closure distal of the capturestructure.
 21. The system of claim 19 wherein the cover has a closedproximal end.
 22. The system of claim 19, wherein a distalmost portionof the inner layer is not collapsed radially inward, so as to form anenlarged distal opening of the cover.
 23. The system of claim 22,wherein the distalmost portion of the inner layer extends proximally inat least partial contact with a radially adjacent portion of the outerlayer.
 24. The system of claim 19, wherein at least the distal region ofthe elongated member comprises a wire.
 25. The system of claim 19,wherein at least the distal region of the elongated member comprises astent retriever.